must theorise
Regular verb: theorise - theorised- theorised

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must theorise
you must theorise
he must theorise
we must theorise
you must theorise
they must theorise 	I must be theorising
you must be theorising
he must be theorising
we must be theorising
you must be theorising
they must be theorising	I must have theorised
you must have theorised
he must have theorised
we must have theorised
you must have theorised
they must have theorised	I must have been theorising
you must have been theorising
he must have been theorising
we must have been theorising
you must have been theorising
they must have been theorising	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't theorise
you mustn't theorise
he mustn't theorise
we mustn't theorise
you mustn't theorise
they mustn't theorise 	I mustn't be theorising
you mustn't be theorising
he mustn't be theorising
we mustn't be theorising
you mustn't be theorising
they mustn't be theorising	I mustn't have theorised
you mustn't have theorised
he mustn't have theorised
we mustn't have theorised
you mustn't have theorised
they mustn't have theorised	I mustn't have been theorising
you mustn't have been theorising
he mustn't have been theorising
we mustn't have been theorising
you mustn't have been theorising
they mustn't have been theorising	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I theorise?
must you theorise?
must he theorise?
must we theorise?
must you theorise?
must they theorise? 	must I be theorising?
must you be theorising?
must he be theorising?
must we be theorising?
must you be theorising?
must they be theorising? 	must I have theorised?
must you have theorised?
must he have theorised?
must we have theorised?
must you have theorised?
must they have theorised? 	must I have been theorising?
must you have been theorising?
must he have been theorising?
must we have been theorising?
must you have been theorising?
must they have been theorising? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I theorise?
mustn't you theorise?
mustn't he theorise?
mustn't we theorise?
mustn't you theorise?
mustn't they theorise? 	mustn't I be theorising?
mustn't you be theorising?
mustn't he be theorising?
mustn't we be theorising?
mustn't you be theorising?
mustn't they be theorising? 	mustn't I have theorised?
mustn't you have theorised?
mustn't he have theorised?
mustn't we have theorised?
mustn't you have theorised?
mustn't they have theorised? 	mustn't I have been theorising?
mustn't you have been theorising?
mustn't he have been theorising?
mustn't we have been theorising?
mustn't you have been theorising?
mustn't they have been theorising?