must last
Regular verb: last - lasted- lasted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must last
you must last
she must last
we must last
you must last
they must last 	I must be lasting
you must be lasting
she must be lasting
we must be lasting
you must be lasting
they must be lasting	I must have lasted
you must have lasted
she must have lasted
we must have lasted
you must have lasted
they must have lasted	I must have been lasting
you must have been lasting
she must have been lasting
we must have been lasting
you must have been lasting
they must have been lasting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not last
you must not last
she must not last
we must not last
you must not last
they must not last 	I must not be lasting
you must not be lasting
she must not be lasting
we must not be lasting
you must not be lasting
they must not be lasting	I must not have lasted
you must not have lasted
she must not have lasted
we must not have lasted
you must not have lasted
they must not have lasted	I must not have been lasting
you must not have been lasting
she must not have been lasting
we must not have been lasting
you must not have been lasting
they must not have been lasting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I last?
must you last?
must she last?
must we last?
must you last?
must they last? 	must I be lasting?
must you be lasting?
must she be lasting?
must we be lasting?
must you be lasting?
must they be lasting? 	must I have lasted?
must you have lasted?
must she have lasted?
must we have lasted?
must you have lasted?
must they have lasted? 	must I have been lasting?
must you have been lasting?
must she have been lasting?
must we have been lasting?
must you have been lasting?
must they have been lasting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not last?
must you not last?
must she not last?
must we not last?
must you not last?
must they not last? 	must I not be lasting?
must you not be lasting?
must she not be lasting?
must we not be lasting?
must you not be lasting?
must they not be lasting? 	must I not have lasted?
must you not have lasted?
must she not have lasted?
must we not have lasted?
must you not have lasted?
must they not have lasted? 	must I not have been lasting?
must you not have been lasting?
must she not have been lasting?
must we not have been lasting?
must you not have been lasting?
must they not have been lasting?