must shift
Regular verb: shift - shifted- shifted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must shift
you must shift
he must shift
we must shift
you must shift
they must shift 	I must be shifting
you must be shifting
he must be shifting
we must be shifting
you must be shifting
they must be shifting	I must have shifted
you must have shifted
he must have shifted
we must have shifted
you must have shifted
they must have shifted	I must have been shifting
you must have been shifting
he must have been shifting
we must have been shifting
you must have been shifting
they must have been shifting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't shift
you mustn't shift
he mustn't shift
we mustn't shift
you mustn't shift
they mustn't shift 	I mustn't be shifting
you mustn't be shifting
he mustn't be shifting
we mustn't be shifting
you mustn't be shifting
they mustn't be shifting	I mustn't have shifted
you mustn't have shifted
he mustn't have shifted
we mustn't have shifted
you mustn't have shifted
they mustn't have shifted	I mustn't have been shifting
you mustn't have been shifting
he mustn't have been shifting
we mustn't have been shifting
you mustn't have been shifting
they mustn't have been shifting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I shift?
must you shift?
must he shift?
must we shift?
must you shift?
must they shift? 	must I be shifting?
must you be shifting?
must he be shifting?
must we be shifting?
must you be shifting?
must they be shifting? 	must I have shifted?
must you have shifted?
must he have shifted?
must we have shifted?
must you have shifted?
must they have shifted? 	must I have been shifting?
must you have been shifting?
must he have been shifting?
must we have been shifting?
must you have been shifting?
must they have been shifting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I shift?
mustn't you shift?
mustn't he shift?
mustn't we shift?
mustn't you shift?
mustn't they shift? 	mustn't I be shifting?
mustn't you be shifting?
mustn't he be shifting?
mustn't we be shifting?
mustn't you be shifting?
mustn't they be shifting? 	mustn't I have shifted?
mustn't you have shifted?
mustn't he have shifted?
mustn't we have shifted?
mustn't you have shifted?
mustn't they have shifted? 	mustn't I have been shifting?
mustn't you have been shifting?
mustn't he have been shifting?
mustn't we have been shifting?
mustn't you have been shifting?
mustn't they have been shifting?