I can enjoy you can enjoy he can enjoy we can enjoy you can enjoy they can enjoy
V-ing form
I can be enjoying you can be enjoying he can be enjoying we can be enjoying you can be enjoying they can be enjoying
Perfect
I can have enjoyed you can have enjoyed he can have enjoyed we can have enjoyed you can have enjoyed they can have enjoyed
V-ing perfect
I can have been enjoying you can have been enjoying he can have been enjoying we can have been enjoying you can have been enjoying they can have been enjoying
Negation
Simple form
I cannot enjoy you cannot enjoy he cannot enjoy we cannot enjoy you cannot enjoy they cannot enjoy
V-ing form
I cannot be enjoying you cannot be enjoying he cannot be enjoying we cannot be enjoying you cannot be enjoying they cannot be enjoying
Perfect
I cannot have enjoyed you cannot have enjoyed he cannot have enjoyed we cannot have enjoyed you cannot have enjoyed they cannot have enjoyed
V-ing perfect
I cannot have been enjoying you cannot have been enjoying he cannot have been enjoying we cannot have been enjoying you cannot have been enjoying they cannot have been enjoying
Interrogative form
Simple form
can I enjoy? can you enjoy? can he enjoy? can we enjoy? can you enjoy? can they enjoy?
V-ing form
can I be enjoying? can you be enjoying? can he be enjoying? can we be enjoying? can you be enjoying? can they be enjoying?
Perfect
can I have enjoyed? can you have enjoyed? can he have enjoyed? can we have enjoyed? can you have enjoyed? can they have enjoyed?
V-ing perfect
can I have been enjoying? can you have been enjoying? can he have been enjoying? can we have been enjoying? can you have been enjoying? can they have been enjoying?
Interro-negative form
Simple form
can I not enjoy? can you not enjoy? can he not enjoy? can we not enjoy? can you not enjoy? can they not enjoy?
V-ing form
can I not be enjoying? can you not be enjoying? can he not be enjoying? can we not be enjoying? can you not be enjoying? can they not be enjoying?
Perfect
can I not have enjoyed? can you not have enjoyed? can he not have enjoyed? can we not have enjoyed? can you not have enjoyed? can they not have enjoyed?
V-ing perfect
can I not have been enjoying? can you not have been enjoying? can he not have been enjoying? can we not have been enjoying? can you not have been enjoying? can they not have been enjoying?