I can jest you can jest he can jest we can jest you can jest they can jest
V-ing form
I can be jesting you can be jesting he can be jesting we can be jesting you can be jesting they can be jesting
Perfect
I can have jested you can have jested he can have jested we can have jested you can have jested they can have jested
V-ing perfect
I can have been jesting you can have been jesting he can have been jesting we can have been jesting you can have been jesting they can have been jesting
Negation
Simple form
I cannot jest you cannot jest he cannot jest we cannot jest you cannot jest they cannot jest
V-ing form
I cannot be jesting you cannot be jesting he cannot be jesting we cannot be jesting you cannot be jesting they cannot be jesting
Perfect
I cannot have jested you cannot have jested he cannot have jested we cannot have jested you cannot have jested they cannot have jested
V-ing perfect
I cannot have been jesting you cannot have been jesting he cannot have been jesting we cannot have been jesting you cannot have been jesting they cannot have been jesting
Interrogative form
Simple form
can I jest? can you jest? can he jest? can we jest? can you jest? can they jest?
V-ing form
can I be jesting? can you be jesting? can he be jesting? can we be jesting? can you be jesting? can they be jesting?
Perfect
can I have jested? can you have jested? can he have jested? can we have jested? can you have jested? can they have jested?
V-ing perfect
can I have been jesting? can you have been jesting? can he have been jesting? can we have been jesting? can you have been jesting? can they have been jesting?
Interro-negative form
Simple form
can I not jest? can you not jest? can he not jest? can we not jest? can you not jest? can they not jest?
V-ing form
can I not be jesting? can you not be jesting? can he not be jesting? can we not be jesting? can you not be jesting? can they not be jesting?
Perfect
can I not have jested? can you not have jested? can he not have jested? can we not have jested? can you not have jested? can they not have jested?
V-ing perfect
can I not have been jesting? can you not have been jesting? can he not have been jesting? can we not have been jesting? can you not have been jesting? can they not have been jesting?