I can reply you can reply he can reply we can reply you can reply they can reply
V-ing form
I can be replying you can be replying he can be replying we can be replying you can be replying they can be replying
Perfect
I can have replied you can have replied he can have replied we can have replied you can have replied they can have replied
V-ing perfect
I can have been replying you can have been replying he can have been replying we can have been replying you can have been replying they can have been replying
Negation
Simple form
I cannot reply you cannot reply he cannot reply we cannot reply you cannot reply they cannot reply
V-ing form
I cannot be replying you cannot be replying he cannot be replying we cannot be replying you cannot be replying they cannot be replying
Perfect
I cannot have replied you cannot have replied he cannot have replied we cannot have replied you cannot have replied they cannot have replied
V-ing perfect
I cannot have been replying you cannot have been replying he cannot have been replying we cannot have been replying you cannot have been replying they cannot have been replying
Interrogative form
Simple form
can I reply? can you reply? can he reply? can we reply? can you reply? can they reply?
V-ing form
can I be replying? can you be replying? can he be replying? can we be replying? can you be replying? can they be replying?
Perfect
can I have replied? can you have replied? can he have replied? can we have replied? can you have replied? can they have replied?
V-ing perfect
can I have been replying? can you have been replying? can he have been replying? can we have been replying? can you have been replying? can they have been replying?
Interro-negative form
Simple form
can I not reply? can you not reply? can he not reply? can we not reply? can you not reply? can they not reply?
V-ing form
can I not be replying? can you not be replying? can he not be replying? can we not be replying? can you not be replying? can they not be replying?
Perfect
can I not have replied? can you not have replied? can he not have replied? can we not have replied? can you not have replied? can they not have replied?
V-ing perfect
can I not have been replying? can you not have been replying? can he not have been replying? can we not have been replying? can you not have been replying? can they not have been replying?