I could square-dance you could square-dance he could square-dance we could square-dance you could square-dance they could square-dance
V-ing form
I could be square-dancing you could be square-dancing he could be square-dancing we could be square-dancing you could be square-dancing they could be square-dancing
Perfect
I could have square-danced you could have square-danced he could have square-danced we could have square-danced you could have square-danced they could have square-danced
V-ing perfect
I could have been square-dancing you could have been square-dancing he could have been square-dancing we could have been square-dancing you could have been square-dancing they could have been square-dancing
Negation
Simple form
I could not square-dance you could not square-dance he could not square-dance we could not square-dance you could not square-dance they could not square-dance
V-ing form
I could not be square-dancing you could not be square-dancing he could not be square-dancing we could not be square-dancing you could not be square-dancing they could not be square-dancing
Perfect
I could not have square-danced you could not have square-danced he could not have square-danced we could not have square-danced you could not have square-danced they could not have square-danced
V-ing perfect
I could not have been square-dancing you could not have been square-dancing he could not have been square-dancing we could not have been square-dancing you could not have been square-dancing they could not have been square-dancing
Interrogative form
Simple form
could I square-dance? could you square-dance? could he square-dance? could we square-dance? could you square-dance? could they square-dance?
V-ing form
could I be square-dancing? could you be square-dancing? could he be square-dancing? could we be square-dancing? could you be square-dancing? could they be square-dancing?
Perfect
could I have square-danced? could you have square-danced? could he have square-danced? could we have square-danced? could you have square-danced? could they have square-danced?
V-ing perfect
could I have been square-dancing? could you have been square-dancing? could he have been square-dancing? could we have been square-dancing? could you have been square-dancing? could they have been square-dancing?
Interro-negative form
Simple form
could I not square-dance? could you not square-dance? could he not square-dance? could we not square-dance? could you not square-dance? could they not square-dance?
V-ing form
could I not be square-dancing? could you not be square-dancing? could he not be square-dancing? could we not be square-dancing? could you not be square-dancing? could they not be square-dancing?
Perfect
could I not have square-danced? could you not have square-danced? could he not have square-danced? could we not have square-danced? could you not have square-danced? could they not have square-danced?
V-ing perfect
could I not have been square-dancing? could you not have been square-dancing? could he not have been square-dancing? could we not have been square-dancing? could you not have been square-dancing? could they not have been square-dancing?