I must postpone you must postpone he must postpone we must postpone you must postpone they must postpone
V-ing form
I must be postponing you must be postponing he must be postponing we must be postponing you must be postponing they must be postponing
Perfect
I must have postponed you must have postponed he must have postponed we must have postponed you must have postponed they must have postponed
V-ing perfect
I must have been postponing you must have been postponing he must have been postponing we must have been postponing you must have been postponing they must have been postponing
Negation
Simple form
I must not postpone you must not postpone he must not postpone we must not postpone you must not postpone they must not postpone
V-ing form
I must not be postponing you must not be postponing he must not be postponing we must not be postponing you must not be postponing they must not be postponing
Perfect
I must not have postponed you must not have postponed he must not have postponed we must not have postponed you must not have postponed they must not have postponed
V-ing perfect
I must not have been postponing you must not have been postponing he must not have been postponing we must not have been postponing you must not have been postponing they must not have been postponing
Interrogative form
Simple form
must I postpone? must you postpone? must he postpone? must we postpone? must you postpone? must they postpone?
V-ing form
must I be postponing? must you be postponing? must he be postponing? must we be postponing? must you be postponing? must they be postponing?
Perfect
must I have postponed? must you have postponed? must he have postponed? must we have postponed? must you have postponed? must they have postponed?
V-ing perfect
must I have been postponing? must you have been postponing? must he have been postponing? must we have been postponing? must you have been postponing? must they have been postponing?
Interro-negative form
Simple form
must I not postpone? must you not postpone? must he not postpone? must we not postpone? must you not postpone? must they not postpone?
V-ing form
must I not be postponing? must you not be postponing? must he not be postponing? must we not be postponing? must you not be postponing? must they not be postponing?
Perfect
must I not have postponed? must you not have postponed? must he not have postponed? must we not have postponed? must you not have postponed? must they not have postponed?
V-ing perfect
must I not have been postponing? must you not have been postponing? must he not have been postponing? must we not have been postponing? must you not have been postponing? must they not have been postponing?