must gain
Regular verb: gain - gained- gained

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must gain
you must gain
she must gain
we must gain
you must gain
they must gain 	I must be gaining
you must be gaining
she must be gaining
we must be gaining
you must be gaining
they must be gaining	I must have gained
you must have gained
she must have gained
we must have gained
you must have gained
they must have gained	I must have been gaining
you must have been gaining
she must have been gaining
we must have been gaining
you must have been gaining
they must have been gaining	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not gain
you must not gain
she must not gain
we must not gain
you must not gain
they must not gain 	I must not be gaining
you must not be gaining
she must not be gaining
we must not be gaining
you must not be gaining
they must not be gaining	I must not have gained
you must not have gained
she must not have gained
we must not have gained
you must not have gained
they must not have gained	I must not have been gaining
you must not have been gaining
she must not have been gaining
we must not have been gaining
you must not have been gaining
they must not have been gaining	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I gain?
must you gain?
must she gain?
must we gain?
must you gain?
must they gain? 	must I be gaining?
must you be gaining?
must she be gaining?
must we be gaining?
must you be gaining?
must they be gaining? 	must I have gained?
must you have gained?
must she have gained?
must we have gained?
must you have gained?
must they have gained? 	must I have been gaining?
must you have been gaining?
must she have been gaining?
must we have been gaining?
must you have been gaining?
must they have been gaining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not gain?
must you not gain?
must she not gain?
must we not gain?
must you not gain?
must they not gain? 	must I not be gaining?
must you not be gaining?
must she not be gaining?
must we not be gaining?
must you not be gaining?
must they not be gaining? 	must I not have gained?
must you not have gained?
must she not have gained?
must we not have gained?
must you not have gained?
must they not have gained? 	must I not have been gaining?
must you not have been gaining?
must she not have been gaining?
must we not have been gaining?
must you not have been gaining?
must they not have been gaining?