must isomerise
Regular verb: isomerise - isomerised- isomerised

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must isomerise
you must isomerise
he must isomerise
we must isomerise
you must isomerise
they must isomerise 	I must be isomerising
you must be isomerising
he must be isomerising
we must be isomerising
you must be isomerising
they must be isomerising	I must have isomerised
you must have isomerised
he must have isomerised
we must have isomerised
you must have isomerised
they must have isomerised	I must have been isomerising
you must have been isomerising
he must have been isomerising
we must have been isomerising
you must have been isomerising
they must have been isomerising	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not isomerise
you must not isomerise
he must not isomerise
we must not isomerise
you must not isomerise
they must not isomerise 	I must not be isomerising
you must not be isomerising
he must not be isomerising
we must not be isomerising
you must not be isomerising
they must not be isomerising	I must not have isomerised
you must not have isomerised
he must not have isomerised
we must not have isomerised
you must not have isomerised
they must not have isomerised	I must not have been isomerising
you must not have been isomerising
he must not have been isomerising
we must not have been isomerising
you must not have been isomerising
they must not have been isomerising	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I isomerise?
must you isomerise?
must he isomerise?
must we isomerise?
must you isomerise?
must they isomerise? 	must I be isomerising?
must you be isomerising?
must he be isomerising?
must we be isomerising?
must you be isomerising?
must they be isomerising? 	must I have isomerised?
must you have isomerised?
must he have isomerised?
must we have isomerised?
must you have isomerised?
must they have isomerised? 	must I have been isomerising?
must you have been isomerising?
must he have been isomerising?
must we have been isomerising?
must you have been isomerising?
must they have been isomerising? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not isomerise?
must you not isomerise?
must he not isomerise?
must we not isomerise?
must you not isomerise?
must they not isomerise? 	must I not be isomerising?
must you not be isomerising?
must he not be isomerising?
must we not be isomerising?
must you not be isomerising?
must they not be isomerising? 	must I not have isomerised?
must you not have isomerised?
must he not have isomerised?
must we not have isomerised?
must you not have isomerised?
must they not have isomerised? 	must I not have been isomerising?
must you not have been isomerising?
must he not have been isomerising?
must we not have been isomerising?
must you not have been isomerising?
must they not have been isomerising?