I could quiet you could quiet he could quiet we could quiet you could quiet they could quiet
V-ing form
I could be quieting you could be quieting he could be quieting we could be quieting you could be quieting they could be quieting
Perfect
I could have quieted you could have quieted he could have quieted we could have quieted you could have quieted they could have quieted
V-ing perfect
I could have been quieting you could have been quieting he could have been quieting we could have been quieting you could have been quieting they could have been quieting
Negation
Simple form
I could not quiet you could not quiet he could not quiet we could not quiet you could not quiet they could not quiet
V-ing form
I could not be quieting you could not be quieting he could not be quieting we could not be quieting you could not be quieting they could not be quieting
Perfect
I could not have quieted you could not have quieted he could not have quieted we could not have quieted you could not have quieted they could not have quieted
V-ing perfect
I could not have been quieting you could not have been quieting he could not have been quieting we could not have been quieting you could not have been quieting they could not have been quieting
Interrogative form
Simple form
could I quiet? could you quiet? could he quiet? could we quiet? could you quiet? could they quiet?
V-ing form
could I be quieting? could you be quieting? could he be quieting? could we be quieting? could you be quieting? could they be quieting?
Perfect
could I have quieted? could you have quieted? could he have quieted? could we have quieted? could you have quieted? could they have quieted?
V-ing perfect
could I have been quieting? could you have been quieting? could he have been quieting? could we have been quieting? could you have been quieting? could they have been quieting?
Interro-negative form
Simple form
could I not quiet? could you not quiet? could he not quiet? could we not quiet? could you not quiet? could they not quiet?
V-ing form
could I not be quieting? could you not be quieting? could he not be quieting? could we not be quieting? could you not be quieting? could they not be quieting?
Perfect
could I not have quieted? could you not have quieted? could he not have quieted? could we not have quieted? could you not have quieted? could they not have quieted?
V-ing perfect
could I not have been quieting? could you not have been quieting? could he not have been quieting? could we not have been quieting? could you not have been quieting? could they not have been quieting?