Verb Sequence in Finite Verb Phrases-3 (perfective)

The "grammar sandwiches" (HAVE__EN, BE__ING, BE__EN) in a verb phrase interlock with each other.

Remember that morphemes are the smallest basic units of meaning, less than (such as -er) or equal to words (such as teach), so a word such as teacher is made of two morphemes: teach and -er.

HAVE and -EN are two morphemes. When they are put together with another verb, they form a perfective: have eaten, has sung, had written. Remember that tense always combines with the first verb:

Perfective structure: three examples, morpheme by morpheme