must swim
Irregular verb: swim - swam- swum

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must swim
you must swim
she must swim
we must swim
you must swim
they must swim 	I must be swimming
you must be swimming
she must be swimming
we must be swimming
you must be swimming
they must be swimming	I must have swum
you must have swum
she must have swum
we must have swum
you must have swum
they must have swum	I must have been swimming
you must have been swimming
she must have been swimming
we must have been swimming
you must have been swimming
they must have been swimming	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't swim
you mustn't swim
she mustn't swim
we mustn't swim
you mustn't swim
they mustn't swim 	I mustn't be swimming
you mustn't be swimming
she mustn't be swimming
we mustn't be swimming
you mustn't be swimming
they mustn't be swimming	I mustn't have swum
you mustn't have swum
she mustn't have swum
we mustn't have swum
you mustn't have swum
they mustn't have swum	I mustn't have been swimming
you mustn't have been swimming
she mustn't have been swimming
we mustn't have been swimming
you mustn't have been swimming
they mustn't have been swimming	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I swim?
must you swim?
must she swim?
must we swim?
must you swim?
must they swim? 	must I be swimming?
must you be swimming?
must she be swimming?
must we be swimming?
must you be swimming?
must they be swimming? 	must I have swum?
must you have swum?
must she have swum?
must we have swum?
must you have swum?
must they have swum? 	must I have been swimming?
must you have been swimming?
must she have been swimming?
must we have been swimming?
must you have been swimming?
must they have been swimming? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I swim?
mustn't you swim?
mustn't she swim?
mustn't we swim?
mustn't you swim?
mustn't they swim? 	mustn't I be swimming?
mustn't you be swimming?
mustn't she be swimming?
mustn't we be swimming?
mustn't you be swimming?
mustn't they be swimming? 	mustn't I have swum?
mustn't you have swum?
mustn't she have swum?
mustn't we have swum?
mustn't you have swum?
mustn't they have swum? 	mustn't I have been swimming?
mustn't you have been swimming?
mustn't she have been swimming?
mustn't we have been swimming?
mustn't you have been swimming?
mustn't they have been swimming?