I must decide you must decide he must decide we must decide you must decide they must decide
V-ing form
I must be deciding you must be deciding he must be deciding we must be deciding you must be deciding they must be deciding
Perfect
I must have decided you must have decided he must have decided we must have decided you must have decided they must have decided
V-ing perfect
I must have been deciding you must have been deciding he must have been deciding we must have been deciding you must have been deciding they must have been deciding
Negation
Simple form
I must not decide you must not decide he must not decide we must not decide you must not decide they must not decide
V-ing form
I must not be deciding you must not be deciding he must not be deciding we must not be deciding you must not be deciding they must not be deciding
Perfect
I must not have decided you must not have decided he must not have decided we must not have decided you must not have decided they must not have decided
V-ing perfect
I must not have been deciding you must not have been deciding he must not have been deciding we must not have been deciding you must not have been deciding they must not have been deciding
Interrogative form
Simple form
must I decide? must you decide? must he decide? must we decide? must you decide? must they decide?
V-ing form
must I be deciding? must you be deciding? must he be deciding? must we be deciding? must you be deciding? must they be deciding?
Perfect
must I have decided? must you have decided? must he have decided? must we have decided? must you have decided? must they have decided?
V-ing perfect
must I have been deciding? must you have been deciding? must he have been deciding? must we have been deciding? must you have been deciding? must they have been deciding?
Interro-negative form
Simple form
must I not decide? must you not decide? must he not decide? must we not decide? must you not decide? must they not decide?
V-ing form
must I not be deciding? must you not be deciding? must he not be deciding? must we not be deciding? must you not be deciding? must they not be deciding?
Perfect
must I not have decided? must you not have decided? must he not have decided? must we not have decided? must you not have decided? must they not have decided?
V-ing perfect
must I not have been deciding? must you not have been deciding? must he not have been deciding? must we not have been deciding? must you not have been deciding? must they not have been deciding?