I must spin you must spin she must spin we must spin you must spin they must spin
V-ing form
I must be spinning you must be spinning she must be spinning we must be spinning you must be spinning they must be spinning
Perfect
I must have spun you must have spun she must have spun we must have spun you must have spun they must have spun
V-ing perfect
I must have been spinning you must have been spinning she must have been spinning we must have been spinning you must have been spinning they must have been spinning
Negation
Simple form
I must not spin you must not spin she must not spin we must not spin you must not spin they must not spin
V-ing form
I must not be spinning you must not be spinning she must not be spinning we must not be spinning you must not be spinning they must not be spinning
Perfect
I must not have spun you must not have spun she must not have spun we must not have spun you must not have spun they must not have spun
V-ing perfect
I must not have been spinning you must not have been spinning she must not have been spinning we must not have been spinning you must not have been spinning they must not have been spinning
Interrogative form
Simple form
must I spin? must you spin? must she spin? must we spin? must you spin? must they spin?
V-ing form
must I be spinning? must you be spinning? must she be spinning? must we be spinning? must you be spinning? must they be spinning?
Perfect
must I have spun? must you have spun? must she have spun? must we have spun? must you have spun? must they have spun?
V-ing perfect
must I have been spinning? must you have been spinning? must she have been spinning? must we have been spinning? must you have been spinning? must they have been spinning?
Interro-negative form
Simple form
must I not spin? must you not spin? must she not spin? must we not spin? must you not spin? must they not spin?
V-ing form
must I not be spinning? must you not be spinning? must she not be spinning? must we not be spinning? must you not be spinning? must they not be spinning?
Perfect
must I not have spun? must you not have spun? must she not have spun? must we not have spun? must you not have spun? must they not have spun?
V-ing perfect
must I not have been spinning? must you not have been spinning? must she not have been spinning? must we not have been spinning? must you not have been spinning? must they not have been spinning?