must sterilise
Regular verb: sterilise - sterilised- sterilised

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must sterilise
you must sterilise
she must sterilise
we must sterilise
you must sterilise
they must sterilise 	I must be sterilising
you must be sterilising
she must be sterilising
we must be sterilising
you must be sterilising
they must be sterilising	I must have sterilised
you must have sterilised
she must have sterilised
we must have sterilised
you must have sterilised
they must have sterilised	I must have been sterilising
you must have been sterilising
she must have been sterilising
we must have been sterilising
you must have been sterilising
they must have been sterilising	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not sterilise
you must not sterilise
she must not sterilise
we must not sterilise
you must not sterilise
they must not sterilise 	I must not be sterilising
you must not be sterilising
she must not be sterilising
we must not be sterilising
you must not be sterilising
they must not be sterilising	I must not have sterilised
you must not have sterilised
she must not have sterilised
we must not have sterilised
you must not have sterilised
they must not have sterilised	I must not have been sterilising
you must not have been sterilising
she must not have been sterilising
we must not have been sterilising
you must not have been sterilising
they must not have been sterilising	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I sterilise?
must you sterilise?
must she sterilise?
must we sterilise?
must you sterilise?
must they sterilise? 	must I be sterilising?
must you be sterilising?
must she be sterilising?
must we be sterilising?
must you be sterilising?
must they be sterilising? 	must I have sterilised?
must you have sterilised?
must she have sterilised?
must we have sterilised?
must you have sterilised?
must they have sterilised? 	must I have been sterilising?
must you have been sterilising?
must she have been sterilising?
must we have been sterilising?
must you have been sterilising?
must they have been sterilising? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not sterilise?
must you not sterilise?
must she not sterilise?
must we not sterilise?
must you not sterilise?
must they not sterilise? 	must I not be sterilising?
must you not be sterilising?
must she not be sterilising?
must we not be sterilising?
must you not be sterilising?
must they not be sterilising? 	must I not have sterilised?
must you not have sterilised?
must she not have sterilised?
must we not have sterilised?
must you not have sterilised?
must they not have sterilised? 	must I not have been sterilising?
must you not have been sterilising?
must she not have been sterilising?
must we not have been sterilising?
must you not have been sterilising?
must they not have been sterilising?