I must free you must free she must free we must free you must free they must free
V-ing form
I must be freeing you must be freeing she must be freeing we must be freeing you must be freeing they must be freeing
Perfect
I must have freed you must have freed she must have freed we must have freed you must have freed they must have freed
V-ing perfect
I must have been freeing you must have been freeing she must have been freeing we must have been freeing you must have been freeing they must have been freeing
Negation
Simple form
I must not free you must not free she must not free we must not free you must not free they must not free
V-ing form
I must not be freeing you must not be freeing she must not be freeing we must not be freeing you must not be freeing they must not be freeing
Perfect
I must not have freed you must not have freed she must not have freed we must not have freed you must not have freed they must not have freed
V-ing perfect
I must not have been freeing you must not have been freeing she must not have been freeing we must not have been freeing you must not have been freeing they must not have been freeing
Interrogative form
Simple form
must I free? must you free? must she free? must we free? must you free? must they free?
V-ing form
must I be freeing? must you be freeing? must she be freeing? must we be freeing? must you be freeing? must they be freeing?
Perfect
must I have freed? must you have freed? must she have freed? must we have freed? must you have freed? must they have freed?
V-ing perfect
must I have been freeing? must you have been freeing? must she have been freeing? must we have been freeing? must you have been freeing? must they have been freeing?
Interro-negative form
Simple form
must I not free? must you not free? must she not free? must we not free? must you not free? must they not free?
V-ing form
must I not be freeing? must you not be freeing? must she not be freeing? must we not be freeing? must you not be freeing? must they not be freeing?
Perfect
must I not have freed? must you not have freed? must she not have freed? must we not have freed? must you not have freed? must they not have freed?
V-ing perfect
must I not have been freeing? must you not have been freeing? must she not have been freeing? must we not have been freeing? must you not have been freeing? must they not have been freeing?