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