I must pucker you must pucker she must pucker we must pucker you must pucker they must pucker
V-ing form
I must be puckering you must be puckering she must be puckering we must be puckering you must be puckering they must be puckering
Perfect
I must have puckered you must have puckered she must have puckered we must have puckered you must have puckered they must have puckered
V-ing perfect
I must have been puckering you must have been puckering she must have been puckering we must have been puckering you must have been puckering they must have been puckering
Negation
Simple form
I must not pucker you must not pucker she must not pucker we must not pucker you must not pucker they must not pucker
V-ing form
I must not be puckering you must not be puckering she must not be puckering we must not be puckering you must not be puckering they must not be puckering
Perfect
I must not have puckered you must not have puckered she must not have puckered we must not have puckered you must not have puckered they must not have puckered
V-ing perfect
I must not have been puckering you must not have been puckering she must not have been puckering we must not have been puckering you must not have been puckering they must not have been puckering
Interrogative form
Simple form
must I pucker? must you pucker? must she pucker? must we pucker? must you pucker? must they pucker?
V-ing form
must I be puckering? must you be puckering? must she be puckering? must we be puckering? must you be puckering? must they be puckering?
Perfect
must I have puckered? must you have puckered? must she have puckered? must we have puckered? must you have puckered? must they have puckered?
V-ing perfect
must I have been puckering? must you have been puckering? must she have been puckering? must we have been puckering? must you have been puckering? must they have been puckering?
Interro-negative form
Simple form
must I not pucker? must you not pucker? must she not pucker? must we not pucker? must you not pucker? must they not pucker?
V-ing form
must I not be puckering? must you not be puckering? must she not be puckering? must we not be puckering? must you not be puckering? must they not be puckering?
Perfect
must I not have puckered? must you not have puckered? must she not have puckered? must we not have puckered? must you not have puckered? must they not have puckered?
V-ing perfect
must I not have been puckering? must you not have been puckering? must she not have been puckering? must we not have been puckering? must you not have been puckering? must they not have been puckering?