I could twirl you could twirl he could twirl we could twirl you could twirl they could twirl
V-ing form
I could be twirling you could be twirling he could be twirling we could be twirling you could be twirling they could be twirling
Perfect
I could have twirled you could have twirled he could have twirled we could have twirled you could have twirled they could have twirled
V-ing perfect
I could have been twirling you could have been twirling he could have been twirling we could have been twirling you could have been twirling they could have been twirling
Negation
Simple form
I could not twirl you could not twirl he could not twirl we could not twirl you could not twirl they could not twirl
V-ing form
I could not be twirling you could not be twirling he could not be twirling we could not be twirling you could not be twirling they could not be twirling
Perfect
I could not have twirled you could not have twirled he could not have twirled we could not have twirled you could not have twirled they could not have twirled
V-ing perfect
I could not have been twirling you could not have been twirling he could not have been twirling we could not have been twirling you could not have been twirling they could not have been twirling
Interrogative form
Simple form
could I twirl? could you twirl? could he twirl? could we twirl? could you twirl? could they twirl?
V-ing form
could I be twirling? could you be twirling? could he be twirling? could we be twirling? could you be twirling? could they be twirling?
Perfect
could I have twirled? could you have twirled? could he have twirled? could we have twirled? could you have twirled? could they have twirled?
V-ing perfect
could I have been twirling? could you have been twirling? could he have been twirling? could we have been twirling? could you have been twirling? could they have been twirling?
Interro-negative form
Simple form
could I not twirl? could you not twirl? could he not twirl? could we not twirl? could you not twirl? could they not twirl?
V-ing form
could I not be twirling? could you not be twirling? could he not be twirling? could we not be twirling? could you not be twirling? could they not be twirling?
Perfect
could I not have twirled? could you not have twirled? could he not have twirled? could we not have twirled? could you not have twirled? could they not have twirled?
V-ing perfect
could I not have been twirling? could you not have been twirling? could he not have been twirling? could we not have been twirling? could you not have been twirling? could they not have been twirling?