I can strum you can strum he can strum we can strum you can strum they can strum
V-ing form
I can be strumming you can be strumming he can be strumming we can be strumming you can be strumming they can be strumming
Perfect
I can have strummed you can have strummed he can have strummed we can have strummed you can have strummed they can have strummed
V-ing perfect
I can have been strumming you can have been strumming he can have been strumming we can have been strumming you can have been strumming they can have been strumming
Negation
Simple form
I cannot strum you cannot strum he cannot strum we cannot strum you cannot strum they cannot strum
V-ing form
I cannot be strumming you cannot be strumming he cannot be strumming we cannot be strumming you cannot be strumming they cannot be strumming
Perfect
I cannot have strummed you cannot have strummed he cannot have strummed we cannot have strummed you cannot have strummed they cannot have strummed
V-ing perfect
I cannot have been strumming you cannot have been strumming he cannot have been strumming we cannot have been strumming you cannot have been strumming they cannot have been strumming
Interrogative form
Simple form
can I strum? can you strum? can he strum? can we strum? can you strum? can they strum?
V-ing form
can I be strumming? can you be strumming? can he be strumming? can we be strumming? can you be strumming? can they be strumming?
Perfect
can I have strummed? can you have strummed? can he have strummed? can we have strummed? can you have strummed? can they have strummed?
V-ing perfect
can I have been strumming? can you have been strumming? can he have been strumming? can we have been strumming? can you have been strumming? can they have been strumming?
Interro-negative form
Simple form
can I not strum? can you not strum? can he not strum? can we not strum? can you not strum? can they not strum?
V-ing form
can I not be strumming? can you not be strumming? can he not be strumming? can we not be strumming? can you not be strumming? can they not be strumming?
Perfect
can I not have strummed? can you not have strummed? can he not have strummed? can we not have strummed? can you not have strummed? can they not have strummed?
V-ing perfect
can I not have been strumming? can you not have been strumming? can he not have been strumming? can we not have been strumming? can you not have been strumming? can they not have been strumming?