I could mend you could mend he could mend we could mend you could mend they could mend
V-ing form
I could be mending you could be mending he could be mending we could be mending you could be mending they could be mending
Perfect
I could have mended you could have mended he could have mended we could have mended you could have mended they could have mended
V-ing perfect
I could have been mending you could have been mending he could have been mending we could have been mending you could have been mending they could have been mending
Negation
Simple form
I could not mend you could not mend he could not mend we could not mend you could not mend they could not mend
V-ing form
I could not be mending you could not be mending he could not be mending we could not be mending you could not be mending they could not be mending
Perfect
I could not have mended you could not have mended he could not have mended we could not have mended you could not have mended they could not have mended
V-ing perfect
I could not have been mending you could not have been mending he could not have been mending we could not have been mending you could not have been mending they could not have been mending
Interrogative form
Simple form
could I mend? could you mend? could he mend? could we mend? could you mend? could they mend?
V-ing form
could I be mending? could you be mending? could he be mending? could we be mending? could you be mending? could they be mending?
Perfect
could I have mended? could you have mended? could he have mended? could we have mended? could you have mended? could they have mended?
V-ing perfect
could I have been mending? could you have been mending? could he have been mending? could we have been mending? could you have been mending? could they have been mending?
Interro-negative form
Simple form
could I not mend? could you not mend? could he not mend? could we not mend? could you not mend? could they not mend?
V-ing form
could I not be mending? could you not be mending? could he not be mending? could we not be mending? could you not be mending? could they not be mending?
Perfect
could I not have mended? could you not have mended? could he not have mended? could we not have mended? could you not have mended? could they not have mended?
V-ing perfect
could I not have been mending? could you not have been mending? could he not have been mending? could we not have been mending? could you not have been mending? could they not have been mending?