The sentence pattern of ‘they are in love with each other’ is

derivational suffix

derivational infix

bound base

inflectional suffix

derivational infix

bound base

inflectional suffix

derivational infix

bound base

joining two or more words together

joining two or more morphemes together

mixing two words into one

annexing prefixes to a base

adding suffixes to a base

adding affixes to a base

joining two or more words together

cutting off parts of two words

adding affixes to the stem

using the initials of a series of words

cutting off parts of two words

adding affixes to the stem

morpheme occurring in the middle of a word

morpheme added after a stem

bound base at the beginning of a word

derivational suffix

derivational infix

bound base

inflectional suffix

derivational infix

bound base

derivational suffix

derivational infix

bound base

inflectional suffix

derivational infix

bound base

derivational suffix

derivational infix

bound base

inflectional suffix

derivational infix

bound base

inflectional suffix

derivational infix

bound base