must collaborate
Regular verb: collaborate - collaborated- collaborated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must collaborate
you must collaborate
she must collaborate
we must collaborate
you must collaborate
they must collaborate 	I must be collaborating
you must be collaborating
she must be collaborating
we must be collaborating
you must be collaborating
they must be collaborating	I must have collaborated
you must have collaborated
she must have collaborated
we must have collaborated
you must have collaborated
they must have collaborated	I must have been collaborating
you must have been collaborating
she must have been collaborating
we must have been collaborating
you must have been collaborating
they must have been collaborating	

Negation 	
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I must not collaborate
you must not collaborate
she must not collaborate
we must not collaborate
you must not collaborate
they must not collaborate 	I must not be collaborating
you must not be collaborating
she must not be collaborating
we must not be collaborating
you must not be collaborating
they must not be collaborating	I must not have collaborated
you must not have collaborated
she must not have collaborated
we must not have collaborated
you must not have collaborated
they must not have collaborated	I must not have been collaborating
you must not have been collaborating
she must not have been collaborating
we must not have been collaborating
you must not have been collaborating
they must not have been collaborating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I collaborate?
must you collaborate?
must she collaborate?
must we collaborate?
must you collaborate?
must they collaborate? 	must I be collaborating?
must you be collaborating?
must she be collaborating?
must we be collaborating?
must you be collaborating?
must they be collaborating? 	must I have collaborated?
must you have collaborated?
must she have collaborated?
must we have collaborated?
must you have collaborated?
must they have collaborated? 	must I have been collaborating?
must you have been collaborating?
must she have been collaborating?
must we have been collaborating?
must you have been collaborating?
must they have been collaborating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not collaborate?
must you not collaborate?
must she not collaborate?
must we not collaborate?
must you not collaborate?
must they not collaborate? 	must I not be collaborating?
must you not be collaborating?
must she not be collaborating?
must we not be collaborating?
must you not be collaborating?
must they not be collaborating? 	must I not have collaborated?
must you not have collaborated?
must she not have collaborated?
must we not have collaborated?
must you not have collaborated?
must they not have collaborated? 	must I not have been collaborating?
must you not have been collaborating?
must she not have been collaborating?
must we not have been collaborating?
must you not have been collaborating?
must they not have been collaborating?