I could charge you could charge she could charge we could charge you could charge they could charge
V-ing form
I could be charging you could be charging she could be charging we could be charging you could be charging they could be charging
Perfect
I could have charged you could have charged she could have charged we could have charged you could have charged they could have charged
V-ing perfect
I could have been charging you could have been charging she could have been charging we could have been charging you could have been charging they could have been charging
Negation
Simple form
I could not charge you could not charge she could not charge we could not charge you could not charge they could not charge
V-ing form
I could not be charging you could not be charging she could not be charging we could not be charging you could not be charging they could not be charging
Perfect
I could not have charged you could not have charged she could not have charged we could not have charged you could not have charged they could not have charged
V-ing perfect
I could not have been charging you could not have been charging she could not have been charging we could not have been charging you could not have been charging they could not have been charging
Interrogative form
Simple form
could I charge? could you charge? could she charge? could we charge? could you charge? could they charge?
V-ing form
could I be charging? could you be charging? could she be charging? could we be charging? could you be charging? could they be charging?
Perfect
could I have charged? could you have charged? could she have charged? could we have charged? could you have charged? could they have charged?
V-ing perfect
could I have been charging? could you have been charging? could she have been charging? could we have been charging? could you have been charging? could they have been charging?
Interro-negative form
Simple form
could I not charge? could you not charge? could she not charge? could we not charge? could you not charge? could they not charge?
V-ing form
could I not be charging? could you not be charging? could she not be charging? could we not be charging? could you not be charging? could they not be charging?
Perfect
could I not have charged? could you not have charged? could she not have charged? could we not have charged? could you not have charged? could they not have charged?
V-ing perfect
could I not have been charging? could you not have been charging? could she not have been charging? could we not have been charging? could you not have been charging? could they not have been charging?