I must explain you must explain she must explain we must explain you must explain they must explain
V-ing form
I must be explaining you must be explaining she must be explaining we must be explaining you must be explaining they must be explaining
Perfect
I must have explained you must have explained she must have explained we must have explained you must have explained they must have explained
V-ing perfect
I must have been explaining you must have been explaining she must have been explaining we must have been explaining you must have been explaining they must have been explaining
Negation
Simple form
I must not explain you must not explain she must not explain we must not explain you must not explain they must not explain
V-ing form
I must not be explaining you must not be explaining she must not be explaining we must not be explaining you must not be explaining they must not be explaining
Perfect
I must not have explained you must not have explained she must not have explained we must not have explained you must not have explained they must not have explained
V-ing perfect
I must not have been explaining you must not have been explaining she must not have been explaining we must not have been explaining you must not have been explaining they must not have been explaining
Interrogative form
Simple form
must I explain? must you explain? must she explain? must we explain? must you explain? must they explain?
V-ing form
must I be explaining? must you be explaining? must she be explaining? must we be explaining? must you be explaining? must they be explaining?
Perfect
must I have explained? must you have explained? must she have explained? must we have explained? must you have explained? must they have explained?
V-ing perfect
must I have been explaining? must you have been explaining? must she have been explaining? must we have been explaining? must you have been explaining? must they have been explaining?
Interro-negative form
Simple form
must I not explain? must you not explain? must she not explain? must we not explain? must you not explain? must they not explain?
V-ing form
must I not be explaining? must you not be explaining? must she not be explaining? must we not be explaining? must you not be explaining? must they not be explaining?
Perfect
must I not have explained? must you not have explained? must she not have explained? must we not have explained? must you not have explained? must they not have explained?
V-ing perfect
must I not have been explaining? must you not have been explaining? must she not have been explaining? must we not have been explaining? must you not have been explaining? must they not have been explaining?