I could rethink you could rethink he could rethink we could rethink you could rethink they could rethink
V-ing form
I could be rethinking you could be rethinking he could be rethinking we could be rethinking you could be rethinking they could be rethinking
Perfect
I could have rethought you could have rethought he could have rethought we could have rethought you could have rethought they could have rethought
V-ing perfect
I could have been rethinking you could have been rethinking he could have been rethinking we could have been rethinking you could have been rethinking they could have been rethinking
Negation
Simple form
I could not rethink you could not rethink he could not rethink we could not rethink you could not rethink they could not rethink
V-ing form
I could not be rethinking you could not be rethinking he could not be rethinking we could not be rethinking you could not be rethinking they could not be rethinking
Perfect
I could not have rethought you could not have rethought he could not have rethought we could not have rethought you could not have rethought they could not have rethought
V-ing perfect
I could not have been rethinking you could not have been rethinking he could not have been rethinking we could not have been rethinking you could not have been rethinking they could not have been rethinking
Interrogative form
Simple form
could I rethink? could you rethink? could he rethink? could we rethink? could you rethink? could they rethink?
V-ing form
could I be rethinking? could you be rethinking? could he be rethinking? could we be rethinking? could you be rethinking? could they be rethinking?
Perfect
could I have rethought? could you have rethought? could he have rethought? could we have rethought? could you have rethought? could they have rethought?
V-ing perfect
could I have been rethinking? could you have been rethinking? could he have been rethinking? could we have been rethinking? could you have been rethinking? could they have been rethinking?
Interro-negative form
Simple form
could I not rethink? could you not rethink? could he not rethink? could we not rethink? could you not rethink? could they not rethink?
V-ing form
could I not be rethinking? could you not be rethinking? could he not be rethinking? could we not be rethinking? could you not be rethinking? could they not be rethinking?
Perfect
could I not have rethought? could you not have rethought? could he not have rethought? could we not have rethought? could you not have rethought? could they not have rethought?
V-ing perfect
could I not have been rethinking? could you not have been rethinking? could he not have been rethinking? could we not have been rethinking? could you not have been rethinking? could they not have been rethinking?