Tài liệu về thì | Anh văn chuyên ngành | Đại học Khoa học Xã hội và Nhân văn, Đại học Quốc gia Thành phố HCM

Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
PRESENT TENSES (Các thì Hiện tại) Thì Công thức
Dấu hiệu nhận biết Cách dùng - BE: - always, usually, often,
- sự thật hiển nhiên (general truth)
S + am / is / are (+ not)
sometimes, seldom, rarely, never, Ex: Water boils at 100 oC SIMPLE
Am / Is / Are + S + …?
every, normally, regularly,
- thói quen (habits, routines) PRESENT
occasionally, as a rule, once /
- tình trạng vĩnh viễn (permanent state) hiện tại - V thường: twice/ three times a
Ex: I live in Vietnam đơn S + V(s/es) week/month/year, in the
- Lịch trình tàu chạy, máy bay bay…
S + don’t/ doesn’t + V1 mornings/ evenings/ on
(schedules, programmed events in the
Do / Does + S + V1 …? Mondays/Tuesdays … future…)
Ex: The plane takes off at 10 tomorrow - instructions,directions
Ex: To go to my house, turn left S + am/is/are + V-ing
- at the moment, now, right now,
- hành động đang diễn ra ngay tại/ xoay at present, still, currently
quanh thời điểm nói.
S + am/ is/ are + not + V-
- Look!, Listen!, Be quiet!, Keep - fixed arrangements ing silent!
Ex: I’m having a party next week. PRESENT
Note: một số động
từ thường - hành động/ thói quen tạm thời [“these CONT
Am / Is /Are + S + V-ing?
không dùng với thì tiếp diễn: like, days”, “but today”] hiện tại tiếp diễn
dislike, hate, love, want, prefer,
Ex: I usually go to school by bus, but today admire, believe,
understand, I’m walking to school.
remember, forget, know, belong, - annoying habits [“always”] have, taste, smell,
Ex: She’s always get ting up late. - change/ development
Ex: The weather is getting worse S + has / have + V3/ed
- lately, recently (gần đây)
- vừa mới xảy ra trong quá khứ, kg có thời
- so far, up to/till now, up to the điểm xác định
S + has / have + not + V3/- present (cho tới bây giờ)
Ex: I’ve just lost my keys. PRESENT ed
- in the past (ten) years (trong - diễn ra trong QK & kéo dài đến hiện tại: PERFECT mười năm qua)
Ex: I’ve worked here since 1999. hiện tại
Has / Have + S + V3/-ed?
- in the last (years) (những năm - tổng kết số lần (làm 1 việc, xem 1 phim, hoàn gần đây)
đọc sách…)/ số công việc [“several times”, thành
- all my / his / her / their … life “many times”]
- already, ever, never, just, [ “never…before”] not…yet, for, since,
Ex: I’ve read that book several times. - how long …
- Nhấn mạnh tính hoàn tất
- This is the first time/second Ex: I have already seen that film time…
PRESENT S + has / have + been + V- - for + khoảng th/g + now (for
- 1 tình trạng (state) từ QK kéo dài liên tục PERFECT ing
two hours now, for three years đến hiện tại và kg gián đoạn CONT
S + has / have + not + been now …)
Ex: It has been raining since 3.00 am hiện tại + V-ing
- Verbs: sit, lie, wait, stay…
- 1 hành động chưa chắc đã hoàn tất hoàn
Note: Không dùng present perfect Ex: I’ve been cleaning the house but I still thành tiếp
Has / Have + S + been + V- cont. với start, begin, finish, stop, haven’t finished. diễn ing …? break 1 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
PAST TENSES (Các thì quá khứ) V to be:
- yesterday, last (last week, last
- hđ xảy ra và hoàn tất trong QK, có thời SIMPLE S + was / were + O
month, last year …), ago, in điểm xác định PAST
S +wasn’t /weren’t+ O
1990, in the past, in 19th century,
Ex: I last met her 10 years ago. quá khứ Was /Were + S + O? in 18 th century, when I was - 1 thói quen trong QK đơn V thường: young…
Ex: When I was young, I usually went S + V2 / V-ed swimming with my family. S + didn’t + V1
- chuỗi hđ liên tiếp trong QK [“when’] Did + S + V1 ….?
Ex: When I went home, I took a shower, had dinner and went to bed
S + was / were + V-ing
- at that time, at (9 o’clock) last
- hđ diễn ra xoay quanh 1 thời điểm xác PAST
S + was / were + not + V-ing night, at this time (last week), in định trong QK CONT Was /Were +S +Ving?
the summer, during the summer,
Ex: I was washing my hair at 7 last night quá khứ
all day, all week, all month, …
- hđ đang diễn ra bị cắt ngang tiếp diễn
[“when”,”while”, “as”]
- 2 hđ diễn ra song song cùng lúc [“while”]
- làm bối cảnh cho 1 câu chuyện
Ex: The sun was shining and the birds were singing. PAST S + had + V3/-ed
- already, ever, never, before, by, - hđ xảy ra trước 1 hđ khác trong QK
PERFECT S + hadn’t + V3/-ed
by the time, after, until, when,
Ex: After I had finished my job, I went quá khứ …. home. hoàn thành Had + S + V3/-ed …?
- hđ xảy ra trước 1 thời điểm trong QK
Ex: I had cleaned my room by 7 last night. PAST
S + had + been + V-ing
- for + khoảng thời gian
- hđ kéo dài liên tục xảy ra trước 1 hđ khác PERFECT
S + hadn’t + been + V-ing trong QK CONT
Ex: After I had been working for 10 hours, quá khứ
Had + S + been + V-ing …? I went home. hoàn thành
- 1 hđ chưa chắc đã hoàn tất xảy ra trước 1 tiếp diễn hđ khác trong QK
Ex: He had been painting the door.
Note: Một số cách hòa hợp thì giữa mệnh đề chính và mệnh đề trạng ngữ thời gian:
1. S.Future + until /when /as soon as/after +
4. Present Perfect + since + Simple Past S.Present/Present Perfect
Ex: I have worked here since I graduated.
Ex: I will phone you when I arrive at the airport.
5. Past Perfect + by the time/before + Simple Past
Ex: I will go home after I have finished my report.
(hành động trước – sau)
2. Simple Past + while / when / as + Past Continuous
Ex: He had left by the time/before I came.
( hành động ngắn – dài)
6. Simple Past + after + Past Perfect
Ex: It started to rain while the boys were playing football.
Ex: I went out after I had finished my homework
3. Past Continuous + while + Past Continuous (hai
hành động song song)
Ex: Last night, I was doing my homework while my sister was playing games.
MỘT SỐ CẤU TRÚC TENSES TRANSFORMATION:
1. I last saw my uncle 10 years ago.
2. This is the first time I have visited
= The last time I saw my uncle was 10 years ago.
Hanoi. = I have never visited Hanoi before.
= It’s/ It has been 10 years since I (last) saw
3. I started/began studying French 2 years my uncle.
ago. = I have studied French for 2 years.
= I haven’t seen my uncle for 10 years 2 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
FUTURE TENSES (Các thì tương lai) Thì Công thức
Dấu hiệu nhận biết Cách dùng S + will / shall + V1 -tomorrow, next,
soon, - hđ sẽ diễn ra trong tương lai SIMPLE
S + will / shall + not + V1 someday, in 2017, …
- quyết định thành lập ngay tại thời FUTURE
(won’t / shan’t + V1)
- I think / guess / hope/ expect… điểm nói tương lai Will / Shall + S + V1? - I am sure / I am not sure - promise, offer, request đơn - in the future
S + am/is/are + (not) +
- kg dùng trong mệnh đề chỉ thời - Future intention (dự định sẵn cho going to V gian tlai) BE
Am/Is/Are + S + going to Ex: We’ll see him when he
Ex: I’m going to visit them next week. GOING V…?
arrives (…when he’s going to - Prediction based on present evidence TO arrive )
Ex: It’s so cloudy. It’s going to rain. Ex: Are you coming tonight?
- Ít dùng với “go”, “come” [→thay = ( Are you going to come? ) Present Cont.] S + will + be + V-ing
- this time tomorrow, this time
- hành động sẽ đang diễn ra xoay next week/month/year
quanh 1 thời điểm trong tương lai
S + will + not + be + V-ing
Ex: I will be lying on the beach this time next year. FUTURE Will + S + be + V-ing?
- future routine, future without CONT intention Tương lai
>< present continuous (deliberate tiếp diễn arrangements)
Ex: I will be seeing Tom tomorrow.
>< I am seeing Tom tomorrow.
S + will + have + V3/-ed - by (by then, by that time, by
- hđ sẽ dược hoàn tất trước 1 thời
24th 2020, by the end of the year, điểm trong tương lai FUTURE
S + will + not + have +
by the end of this month…)
Ex: By 2018, we will have built a PERFECT V3/-ed
house in the neighborhood of Paris. Tương lai hoàn
Will + S + have + V3/-ed? thành
FUTURE S + will have been +V-ing - by (by the end of the
- nhấn mạnh tính liên tục (continuous PERFEC year/month…) action) T CONT.
S + will + not + have been
Ex: By the end of this year, he will Tương lai + V-ing
have been working for 20 years. hoàn
- Note: khi tổng kết số lượng công
thành tiếp Will + S + have been + V-
việc -> Future Perfect , Future Perfect diễn ing? Continuous
Ex: By the end of the month, he will
have climbed 50 mountains/ he will
have been climbing 50 mountains . 3 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL) A B C D E F
Last night I (1)______________ home next to the river Thames, when something strange
(2)______________________ to me. It was late at night and I (3)_______________ a long and difficult day at work.
There was a large full moon in the sky and everything was quiet. I was tired and lonely and I
(4)___________________ a few pints of beer in my local pub, so I decided to stop by the riverside and look at the moon for a while.
I (5)_________________ on some steps very close to the water’s edge and looked up at the big yellow moon and
wondered if it really was made of cheese. I felt very tired so I (6)____________________ my eyes and after a few
minutes, I (7)_________________ asleep. When I woke up, the moon (8)______________________ behind a cloud
and it was very dark and cold. The wind (9)___________________ and an owl (10)___________________ in a tree
above me. I rubbed my eyes and started to get up, when suddenly I (11)_____________________ a splash. ❖Multiple Choice:
8. We ______ exam at 8 o’clock next Monday.
1. He was writing to his friend when he ______a noise. A. will take
B. will be taking C. take D. would
A. was hearing B. heard C. had heard D. hears take
2. I __________many people since I came here in
9. By the end of next year, my son _______ English for June. six months. A. met B. has met C. was meeting D. have A. will learn B. will have learned met C. has learned D. had learned
3. We __________ maths at this time last week.
10. “ How long have you been with the company?” - “
A. were learning B. are learning C. was learning D. learnt
I ______ there for ten years by September”
4. She was playing games while he __________a A. will work B. was working football match. C. will be working D. will have worked
A. watched B. watches C. was watching D. watching
5. I will contact you as soon as I ___________the information. A. will get B. get C. got D. had got
6. When we arrived, the film ______ for five minutes.
A. has started B. had started C. started D. was starting
7. __________he playing football now? A. Will B. Does C. Was D. Is 4 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
FURTHER TENSES EXERCISES
I. Complete the sentence, using either the past simple or past progressive of the verbs in parentheses
1. When Mrs. Chu _______________ (hear) a strange noise, she ________________ (get) up to investigate.
32. AtI_______________________eighto’clocklastnight,(not Ihear)___ the thunder during the storm last night because I ______________________ (sleep).
________________ (practice) the piano.
4. When I _________________ (be) a child, we _____________________ (make) our own amusement
5. It __________________________ (happen) while I _____________________________ (live) in Eastbourne last year.
6. I ___________________ (live)in London 14 years while I __________________________ (be) a child.
7. As I (walk)____________________________down the road, I __________________________ (see) Bill.
8. I got a package in the mail. When I ___________________ (open) it, I ______________________ (find) a surprise.
9. While Jane ____________________ (wash) the dishes, her brothers _________________________ (watch) television.
10. I ____________________ (rewind) the rented video before I_____________________ (return) it to the store yesterday.
11. When he realized I _________________________ (look) at him, he ____________________ (turn) away.
12. Richard _______________________ (live) in Chicago for five years when his company ___________________ (transfer) him to New York.
13. He usually wears sandals but when I last___________________ (see) him he ____________________ (wear) boots.
14. I was alone in the house at that time because Mr. Jones______________________________(work) in the garage and
Mrs. Jones______________________(shop)
15. Jane_____________________ (meet) her husband while she ____________________ (study) law at Harvard
II. Complete these sentences, using the present perfect, present perfect progressive, past perfect
or past perfect progressive.
1. The children are at the park. They ____________ ball for the last two hours, but they don’t seem tired yet. (play)
2. This was the first time we ____________ to the castle, even though we ____________ Edinburgh a few times before (be - visit)
3. He ____________his finger and is in a lot of pain. (break)
4. At last the bus came. I ____________ for 20 minutes. (wait)
5. Good, the noise____________ . I can start concentrating on my work again, (stop)
6. We were extremely tired at the end of the journey. We ____________ for more than 4 hours. (travel)
7. Lisa is still writing letters. She ____________ letters all day. (write)
8. My teacher was really annoyed with me. It was the third time I ____________ late for school that week, (arrive)
9. I ____________ and I feel exhausted. (swim)
10. I ____________ my address book. Have you seen it? (lose)
11. He _____________ football all afternoon and needs a shower! (play) 5 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
12. When I last saw John, he____________________ and was out of breath, (run).
13. We _____________ the car for 6 months before we discovered it was stolen. (own)
14. I ________________ this book on astrophysics for hours and I’m still only on page 6. (read)
15. I _____________ ice cream since I ate too much and was sick, (not like)
III. Underline the correct answer
1. On my last visit to Wixton I found that the village hadn’t changed /didn’t change much.
2. Mark has taken / took many trips to Asia since he has started / started his own importexport business.
3. When I was introduced to Carol, I was sure that I had met / met her before.
4. Argentina has won / won the World Cup in 1986 for the second time since the cup was /has been first awarded in 1930.
5. When the teacher had cornel came in, all the students had stood / stood up.
6. By the time Jackson had arrived / arrived to help, we had already finished / already finished moving everything . 7
.Ican’tcome to your party because I broke / have broken my leg.
8. As soon as I had turned / turned the ignition key, the engine had caught / caught fire.
9. When they got / had got married, they knew / had known each other for 15 years.
10. My brother has written / wrote several plays. He has just finished / just finished his second tragedy.
11. The apartment was hot when I had got / got home, so I had turned / turned on the air conditioner.
12. Ann has started / started a letter to her parents last week, but she still hasn’t finished / didn’t finish it.
13. I knew / have known Tim when he was a child, but I didn’t see / haven’t seen him for many years.
14. It was the fifth time she asked / had asked me the same question.
15. I have read / read his books when I has been / was at school. Have you ever read / Did you ever read his books?
IV. Complete the sentences with the correct form or tense of the verbs in brackets
1. When Glen ____________________ (open) the book, some pages _________________________ (fall) out.
2. Since she ___________________ (work) at the company she __________________ (not have) a day off through illness.
3. It was the first, time I __________________________ (talk) to Ella outside the office.
4. My boss__________ (come) into the office just as I_____________ (show) holiday photos.
5. Mozart ___________________ (die) while he _________________ (compose) the Requiem.
6. At the time of the robbery, they________________________ (stay) with my parents.
7. Mr. Count ___________________ (work) as a cashier for twenty-five years. Then he ______________________ (
retire) and______________________(go) to live in the country.
8. The pollution problem ____________________________ (get) worse over the last decade.
9. I _____________________ (not/ see) Jane for ages. When I last _________________ (see) her, she _________________ (try) to find a job.
10. In a surprise move, the Prime Minister _____________________ (resign) last night.
12. That’sAlexanderthe firstGrahamtimeBellI____________________ (already/ invent) the telephone by the time I was born.
___________________ (see) Jan look embarrassed. 6 lOMoAR cPSD| 39651089
13. I didn’t know who she was. I _____
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL) somebody shoplifting.
her day in Taylor’s the jewelers, when I actually ______ (see)
_________________ (never/ see) her before.
14. I ________________ (buy) a new alarm clock the ot
15. I ________________________ (not like) having Sam for my roommate last/year. He ___________________ (always/
leave). This dirty clothes on the floor.
1. It’s not a deep cut, but it
V. Underline the correct alternatives.
is leaving/ is going to leave a scar.
3. ‘I’m not sure how I’ll get the concert’ ‘We can take you. We
2 Did y u know I am going
buy/ will buy a new c r next week? to
will pick/ are going to pick you up at 8.00.
54. I’mWe sorryget/areIcan’tgoingcometogetforourdinnerexam.I results on the 20th August.
am driving/ will drive to York tonight.
76. Don’tIhavegoto outgonow..IIam going to call! will calllunchyouandbackit’llatbercoldtoayby. the time you will serve am serving get/ will get back., ,
8. I think I will take! take an umbrella in case it, will rain! rains.
9. Unless help arrives within the next few days, thousands are starving! are going to starve.
10. The concert starts/ is going to start at 7.30, not 7.15 as it says in the program.
12. It’sTonightunlikelyFrancethatplay/thegovernmentareplayi Germany in a matchtheimportantcourt’sdecisionforbth. teams. will accept/ accept
13. Before I will go/ go home tonight, I am going to stop/ stop at the market.
14. This chair is too heavy for you to carry alone. I will help! am going to help you.
15. The train will leave/ leaves at 8:15 tomorrow morning, so I am coming! come to the station at 8:00
VI. Complete these sentences with the future form: will + infinitive; the future continuous; the future
? ~I’d love to, but I afraid I________
perfect or future perfect continuous
2. In a hundred years’ time people
1 Will you have lunch with me on 24th
____________ my exam then, (do)
_____________________ to Mars for their holidays, (go)
3. By the end of my university course I _______________________ 1,200 lectures, (attend)
4. Without more cheap housing, families________________________ the village and find homes in town, (leave)
5. Weather forecast says that the rain ____________________by the morning and tomorrow will be dry. (clear)
6. I supposewoyears’by nowtimeschoolMorneau______________________for Christmas and you _______________a rest, (close, enjoy)
87. Don’tIn ring her up at 10 o’clock; she ___________for 50 years and show no sign of retiring from the theater, (act)
_________the children to bed Ring later, (put)
9. This time next Monday I ______________________ in a Paris cafe reading Le Figaro, (sit)
10. am confident that I ______________________the report before the end of the week,itfor(finish)amonth, and I’m still only half
11. This book on Proust is really difficult. On Saturday I _____________ way. (read) ____a lot by the time
13. I’m enjoying the course. I
. I’ve completed it. (learn)
2 _____________________my car until next week, so you can borrow it if you like, (use)
14. I’ve got an exam tomorrow, so I can’t come out tonight ____
15. I’m late with my project. I______
________ it by the time we’re supposed to hand it in. (not finish)
I____________________ all evening, (revise) _______
1. It’s raining right now. As soon as the rain
(stop). I’m going to walk down town.
VII. Put the verb in brackets i to correct form 7 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
2. On arrival at home I _______________ (find) that she______________(leave) just a few minutes before.
4. I’m sorry I couldn’t stop when I
3 He _______________(light) a cigarette and ___________________(walk) to the door.
________ (see) you the other day. I________________ (catch) a train, so I was in a hurry.
5. She___________________ (sleep) for 10 hours! You must wake her.
6. David _________________ (repair) the TV set at the moment. He___________________ (work) at it for one hour or so.
7. Just as I ____________________ (leave) home for school the telephone________________ (ring). buildings.
____ (come) back in two years’ time, they
8. For the last six months I______
(h ve) a job as hospital porter.
9. I suppose when I______________
_____________ (pull) down all these old
10. It’s an hour since he____________________ (leave) his office. So he must be home now.
11. At this time next week they___________________ (sit) in the train on their way to Paris.
12. As soon as I_______________________ (return) to my desk, I_________________ (notice) that my computer
________________________ (make) a funny noise.
13. Pedro______________________ (change) his major three times since h__________(start) school.
14. I____________________ (expect) the mail an hour ago, but it___________________(not/come) yet.
15. While I___________________ (walk) up the mountain, I_____________________ (get) tired. But I (not/stop) until I
_____________________________ (reach) the top.
MULTIPLE CHOICE EXERCISES
1. She said she met you once at the Parade a. will finish b. will be finishing
last week. _____________ since ? c. will have finished d. are finishing
a. Have you met her b. Had you met her
7. We _____ tennis for half an hour when it started c. Did you meet her d. Did you meet her to rain.
2. Several years after they _____ up they met again a. was playing b. has been playing by chance in Paris. c. had been playing d. would be playing a. have split b. had split
8. We __________ at a hotel in Miami when the
c. were split d. had been splitting
hurricane ______ southern Florida last month.
3. By this time tomorrow, Peter_____ for the a. were staying- hit b. stayed hit - was hitting
graduation examination, so now he feels very c. had stayed - hit d. stayed – nervous.
9. I must just go and wash, I ______________ . a. will sit b. is sitting a. have gardened b. have been gardening
10. Alex’s plane _______ at 10:15 tomorrow morning,
c. will be sitting d. will have sitting c. had gardened d. was gardening
4. Please turn off the stove. The water _____ for more than fifteen minutes,
a. but I can’t pick him up. a. is boiling b. was boiling will arrive b. is arriving
c. will be boiling d. has been boiling c. will be arriving d. arrives
5. I am sorry I cannot hear what you ________
11. I ______ Jane tonight, so I will pass your message
because everybody _____so loudly. on to her.
a. are saying - talk b. have just said - is talking a. meet b. will be meeting
c. were saying - has talked d. said - was talking c. am meeting d. will have met
6. They _____ the job by this time tomorrow. 8 lOMoAR cPSD| 39651089
Ms. Dương Ngọc Hoàng Yến (M.A. in TESOL)
12. In every culture, people _____ jewelry
22. I have never played table tennis before. This is since prehistoric times.
the first time I ______ to play.
a. wearI b. Bob’swore cpen.haveto
There’s no point asking John for a a. try b. tried c. have tried d. am trying
himwornthed. nexthad worntime I 13. 23. lift - he ____________him. ____________ by now. a. will return - see b. will return-will see a. is leaving b. will leave c. return - will see d. return see c. will be leaving d. will have left ___________ as a
14. I_______ the time when I first –
24. Before I went to university, I________________as a a. won’t forget teacher.
carpenter for about five years. - work a. worked b. used to work b. will never forget
c. haveIwon’tworkbedable to meetd.wasyouworkingnext worked have worked c. never forget - – 25. week. I _______
I _______on the left because I’ve li d. never forgot - had worked in London for a few days. 15. ved in Britain a. will stay b. will be staying for a long time. c. will have stayed d. am staying a. used to drive b. am used to drive
26. Mary ____ on the essay for two hours now and
c. get used to driving d. am used to driving
she hopes that she ~ it in one more hour.
16. This large goat _____ in the mountains of a. is working -can finish Switzerland.
b. has been working -will finish a. only lives b. is only living
c. will have worked - finishes c. has only lived
d. hadIt’sbeengettingworkingveryhumid-would finish d. only lived
17. Charles is a gifted footballer, but up to now he 27. - we _____ a a. doesn’t play b. didn’t play
well in the international matches. thunderstorm.
a. will have b. are having c. are going to have d. have c. hasn’t placed d. wasn’t playing
28. I _____ a lot of interesting people while I in
18. The committee_____ four times last week, but Norway. c. met - was – was ’working still no decision________ a. met worked meeting
a. met - has been reached b. has met - has reached b. was – c. met is reached d. had met - was reached working
far this week. I ________two tests and a quiz. d. was meeting worked 19. So —
a. had b. have had c. will have d. was having –
29. We _____ for about an hour when the engine
20. _________to the opera when you lived in Milan? suddenly stopped,
a. Have you ever gone b. Were you ever going a. was driving b. have driven c. have been driving c. Did you ever go
d. had been drivingrs.Why don’t d. Had you ever gone
21. I________ one of my special desserts for dinner, if 30.
You ________for five straight hou you like. you take a break.
a. make b. am making c. am going to make d. will make a. Studied b. was studying c. had studied d. have been studying 9