I can chew you can chew he can chew we can chew you can chew they can chew
V-ing form
I can be chewing you can be chewing he can be chewing we can be chewing you can be chewing they can be chewing
Perfect
I can have chewed you can have chewed he can have chewed we can have chewed you can have chewed they can have chewed
V-ing perfect
I can have been chewing you can have been chewing he can have been chewing we can have been chewing you can have been chewing they can have been chewing
Negation
Simple form
I cannot chew you cannot chew he cannot chew we cannot chew you cannot chew they cannot chew
V-ing form
I cannot be chewing you cannot be chewing he cannot be chewing we cannot be chewing you cannot be chewing they cannot be chewing
Perfect
I cannot have chewed you cannot have chewed he cannot have chewed we cannot have chewed you cannot have chewed they cannot have chewed
V-ing perfect
I cannot have been chewing you cannot have been chewing he cannot have been chewing we cannot have been chewing you cannot have been chewing they cannot have been chewing
Interrogative form
Simple form
can I chew? can you chew? can he chew? can we chew? can you chew? can they chew?
V-ing form
can I be chewing? can you be chewing? can he be chewing? can we be chewing? can you be chewing? can they be chewing?
Perfect
can I have chewed? can you have chewed? can he have chewed? can we have chewed? can you have chewed? can they have chewed?
V-ing perfect
can I have been chewing? can you have been chewing? can he have been chewing? can we have been chewing? can you have been chewing? can they have been chewing?
Interro-negative form
Simple form
can I not chew? can you not chew? can he not chew? can we not chew? can you not chew? can they not chew?
V-ing form
can I not be chewing? can you not be chewing? can he not be chewing? can we not be chewing? can you not be chewing? can they not be chewing?
Perfect
can I not have chewed? can you not have chewed? can he not have chewed? can we not have chewed? can you not have chewed? can they not have chewed?
V-ing perfect
can I not have been chewing? can you not have been chewing? can he not have been chewing? can we not have been chewing? can you not have been chewing? can they not have been chewing?