I could put you could put she could put we could put you could put they could put
V-ing form
I could be putting you could be putting she could be putting we could be putting you could be putting they could be putting
Perfect
I could have put you could have put she could have put we could have put you could have put they could have put
V-ing perfect
I could have been putting you could have been putting she could have been putting we could have been putting you could have been putting they could have been putting
Negation
Simple form
I could not put you could not put she could not put we could not put you could not put they could not put
V-ing form
I could not be putting you could not be putting she could not be putting we could not be putting you could not be putting they could not be putting
Perfect
I could not have put you could not have put she could not have put we could not have put you could not have put they could not have put
V-ing perfect
I could not have been putting you could not have been putting she could not have been putting we could not have been putting you could not have been putting they could not have been putting
Interrogative form
Simple form
could I put? could you put? could she put? could we put? could you put? could they put?
V-ing form
could I be putting? could you be putting? could she be putting? could we be putting? could you be putting? could they be putting?
Perfect
could I have put? could you have put? could she have put? could we have put? could you have put? could they have put?
V-ing perfect
could I have been putting? could you have been putting? could she have been putting? could we have been putting? could you have been putting? could they have been putting?
Interro-negative form
Simple form
could I not put? could you not put? could she not put? could we not put? could you not put? could they not put?
V-ing form
could I not be putting? could you not be putting? could she not be putting? could we not be putting? could you not be putting? could they not be putting?
Perfect
could I not have put? could you not have put? could she not have put? could we not have put? could you not have put? could they not have put?
V-ing perfect
could I not have been putting? could you not have been putting? could she not have been putting? could we not have been putting? could you not have been putting? could they not have been putting?