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