According to the definition, morphological aspect presents the reported event or state of affairs as if viewed either from inside the event (‘in progress’) or outside the event (‘as a whole’).
- Perfect Aspect: have + past.participle a. John had eaten an apple. b. John has eaten an apple. c. John will have eaten an apple.
- Progressive Aspect: be + present.participle a. John was eating an apple. b. John is eating an apple. c. John will be eating an apple.
But I'm wondering whether morphological aspect only refers to perfect aspect and progressive aspect? If not, what does this sentence "John eats apple" belong to?