I must close you must close she must close we must close you must close they must close
V-ing form
I must be closing you must be closing she must be closing we must be closing you must be closing they must be closing
Perfect
I must have closed you must have closed she must have closed we must have closed you must have closed they must have closed
V-ing perfect
I must have been closing you must have been closing she must have been closing we must have been closing you must have been closing they must have been closing
Negation
Simple form
I must not close you must not close she must not close we must not close you must not close they must not close
V-ing form
I must not be closing you must not be closing she must not be closing we must not be closing you must not be closing they must not be closing
Perfect
I must not have closed you must not have closed she must not have closed we must not have closed you must not have closed they must not have closed
V-ing perfect
I must not have been closing you must not have been closing she must not have been closing we must not have been closing you must not have been closing they must not have been closing
Interrogative form
Simple form
must I close? must you close? must she close? must we close? must you close? must they close?
V-ing form
must I be closing? must you be closing? must she be closing? must we be closing? must you be closing? must they be closing?
Perfect
must I have closed? must you have closed? must she have closed? must we have closed? must you have closed? must they have closed?
V-ing perfect
must I have been closing? must you have been closing? must she have been closing? must we have been closing? must you have been closing? must they have been closing?
Interro-negative form
Simple form
must I not close? must you not close? must she not close? must we not close? must you not close? must they not close?
V-ing form
must I not be closing? must you not be closing? must she not be closing? must we not be closing? must you not be closing? must they not be closing?
Perfect
must I not have closed? must you not have closed? must she not have closed? must we not have closed? must you not have closed? must they not have closed?
V-ing perfect
must I not have been closing? must you not have been closing? must she not have been closing? must we not have been closing? must you not have been closing? must they not have been closing?