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