I can joke you can joke he can joke we can joke you can joke they can joke
V-ing form
I can be joking you can be joking he can be joking we can be joking you can be joking they can be joking
Perfect
I can have joked you can have joked he can have joked we can have joked you can have joked they can have joked
V-ing perfect
I can have been joking you can have been joking he can have been joking we can have been joking you can have been joking they can have been joking
Negation
Simple form
I cannot joke you cannot joke he cannot joke we cannot joke you cannot joke they cannot joke
V-ing form
I cannot be joking you cannot be joking he cannot be joking we cannot be joking you cannot be joking they cannot be joking
Perfect
I cannot have joked you cannot have joked he cannot have joked we cannot have joked you cannot have joked they cannot have joked
V-ing perfect
I cannot have been joking you cannot have been joking he cannot have been joking we cannot have been joking you cannot have been joking they cannot have been joking
Interrogative form
Simple form
can I joke? can you joke? can he joke? can we joke? can you joke? can they joke?
V-ing form
can I be joking? can you be joking? can he be joking? can we be joking? can you be joking? can they be joking?
Perfect
can I have joked? can you have joked? can he have joked? can we have joked? can you have joked? can they have joked?
V-ing perfect
can I have been joking? can you have been joking? can he have been joking? can we have been joking? can you have been joking? can they have been joking?
Interro-negative form
Simple form
can I not joke? can you not joke? can he not joke? can we not joke? can you not joke? can they not joke?
V-ing form
can I not be joking? can you not be joking? can he not be joking? can we not be joking? can you not be joking? can they not be joking?
Perfect
can I not have joked? can you not have joked? can he not have joked? can we not have joked? can you not have joked? can they not have joked?
V-ing perfect
can I not have been joking? can you not have been joking? can he not have been joking? can we not have been joking? can you not have been joking? can they not have been joking?