must insulate
Regular verb: insulate - insulated- insulated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must insulate
you must insulate
she must insulate
we must insulate
you must insulate
they must insulate 	I must be insulating
you must be insulating
she must be insulating
we must be insulating
you must be insulating
they must be insulating	I must have insulated
you must have insulated
she must have insulated
we must have insulated
you must have insulated
they must have insulated	I must have been insulating
you must have been insulating
she must have been insulating
we must have been insulating
you must have been insulating
they must have been insulating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't insulate
you mustn't insulate
she mustn't insulate
we mustn't insulate
you mustn't insulate
they mustn't insulate 	I mustn't be insulating
you mustn't be insulating
she mustn't be insulating
we mustn't be insulating
you mustn't be insulating
they mustn't be insulating	I mustn't have insulated
you mustn't have insulated
she mustn't have insulated
we mustn't have insulated
you mustn't have insulated
they mustn't have insulated	I mustn't have been insulating
you mustn't have been insulating
she mustn't have been insulating
we mustn't have been insulating
you mustn't have been insulating
they mustn't have been insulating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I insulate?
must you insulate?
must she insulate?
must we insulate?
must you insulate?
must they insulate? 	must I be insulating?
must you be insulating?
must she be insulating?
must we be insulating?
must you be insulating?
must they be insulating? 	must I have insulated?
must you have insulated?
must she have insulated?
must we have insulated?
must you have insulated?
must they have insulated? 	must I have been insulating?
must you have been insulating?
must she have been insulating?
must we have been insulating?
must you have been insulating?
must they have been insulating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I insulate?
mustn't you insulate?
mustn't she insulate?
mustn't we insulate?
mustn't you insulate?
mustn't they insulate? 	mustn't I be insulating?
mustn't you be insulating?
mustn't she be insulating?
mustn't we be insulating?
mustn't you be insulating?
mustn't they be insulating? 	mustn't I have insulated?
mustn't you have insulated?
mustn't she have insulated?
mustn't we have insulated?
mustn't you have insulated?
mustn't they have insulated? 	mustn't I have been insulating?
mustn't you have been insulating?
mustn't she have been insulating?
mustn't we have been insulating?
mustn't you have been insulating?
mustn't they have been insulating?