must corrugate
Regular verb: corrugate - corrugated- corrugated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must corrugate
you must corrugate
he must corrugate
we must corrugate
you must corrugate
they must corrugate 	I must be corrugating
you must be corrugating
he must be corrugating
we must be corrugating
you must be corrugating
they must be corrugating	I must have corrugated
you must have corrugated
he must have corrugated
we must have corrugated
you must have corrugated
they must have corrugated	I must have been corrugating
you must have been corrugating
he must have been corrugating
we must have been corrugating
you must have been corrugating
they must have been corrugating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't corrugate
you mustn't corrugate
he mustn't corrugate
we mustn't corrugate
you mustn't corrugate
they mustn't corrugate 	I mustn't be corrugating
you mustn't be corrugating
he mustn't be corrugating
we mustn't be corrugating
you mustn't be corrugating
they mustn't be corrugating	I mustn't have corrugated
you mustn't have corrugated
he mustn't have corrugated
we mustn't have corrugated
you mustn't have corrugated
they mustn't have corrugated	I mustn't have been corrugating
you mustn't have been corrugating
he mustn't have been corrugating
we mustn't have been corrugating
you mustn't have been corrugating
they mustn't have been corrugating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I corrugate?
must you corrugate?
must he corrugate?
must we corrugate?
must you corrugate?
must they corrugate? 	must I be corrugating?
must you be corrugating?
must he be corrugating?
must we be corrugating?
must you be corrugating?
must they be corrugating? 	must I have corrugated?
must you have corrugated?
must he have corrugated?
must we have corrugated?
must you have corrugated?
must they have corrugated? 	must I have been corrugating?
must you have been corrugating?
must he have been corrugating?
must we have been corrugating?
must you have been corrugating?
must they have been corrugating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I corrugate?
mustn't you corrugate?
mustn't he corrugate?
mustn't we corrugate?
mustn't you corrugate?
mustn't they corrugate? 	mustn't I be corrugating?
mustn't you be corrugating?
mustn't he be corrugating?
mustn't we be corrugating?
mustn't you be corrugating?
mustn't they be corrugating? 	mustn't I have corrugated?
mustn't you have corrugated?
mustn't he have corrugated?
mustn't we have corrugated?
mustn't you have corrugated?
mustn't they have corrugated? 	mustn't I have been corrugating?
mustn't you have been corrugating?
mustn't he have been corrugating?
mustn't we have been corrugating?
mustn't you have been corrugating?
mustn't they have been corrugating?