must skipper
Regular verb: skipper - skippered- skippered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must skipper
you must skipper
she must skipper
we must skipper
you must skipper
they must skipper 	I must be skippering
you must be skippering
she must be skippering
we must be skippering
you must be skippering
they must be skippering	I must have skippered
you must have skippered
she must have skippered
we must have skippered
you must have skippered
they must have skippered	I must have been skippering
you must have been skippering
she must have been skippering
we must have been skippering
you must have been skippering
they must have been skippering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not skipper
you must not skipper
she must not skipper
we must not skipper
you must not skipper
they must not skipper 	I must not be skippering
you must not be skippering
she must not be skippering
we must not be skippering
you must not be skippering
they must not be skippering	I must not have skippered
you must not have skippered
she must not have skippered
we must not have skippered
you must not have skippered
they must not have skippered	I must not have been skippering
you must not have been skippering
she must not have been skippering
we must not have been skippering
you must not have been skippering
they must not have been skippering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I skipper?
must you skipper?
must she skipper?
must we skipper?
must you skipper?
must they skipper? 	must I be skippering?
must you be skippering?
must she be skippering?
must we be skippering?
must you be skippering?
must they be skippering? 	must I have skippered?
must you have skippered?
must she have skippered?
must we have skippered?
must you have skippered?
must they have skippered? 	must I have been skippering?
must you have been skippering?
must she have been skippering?
must we have been skippering?
must you have been skippering?
must they have been skippering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not skipper?
must you not skipper?
must she not skipper?
must we not skipper?
must you not skipper?
must they not skipper? 	must I not be skippering?
must you not be skippering?
must she not be skippering?
must we not be skippering?
must you not be skippering?
must they not be skippering? 	must I not have skippered?
must you not have skippered?
must she not have skippered?
must we not have skippered?
must you not have skippered?
must they not have skippered? 	must I not have been skippering?
must you not have been skippering?
must she not have been skippering?
must we not have been skippering?
must you not have been skippering?
must they not have been skippering?