must billow
Regular verb: billow - billowed- billowed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must billow
you must billow
she must billow
we must billow
you must billow
they must billow 	I must be billowing
you must be billowing
she must be billowing
we must be billowing
you must be billowing
they must be billowing	I must have billowed
you must have billowed
she must have billowed
we must have billowed
you must have billowed
they must have billowed	I must have been billowing
you must have been billowing
she must have been billowing
we must have been billowing
you must have been billowing
they must have been billowing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not billow
you must not billow
she must not billow
we must not billow
you must not billow
they must not billow 	I must not be billowing
you must not be billowing
she must not be billowing
we must not be billowing
you must not be billowing
they must not be billowing	I must not have billowed
you must not have billowed
she must not have billowed
we must not have billowed
you must not have billowed
they must not have billowed	I must not have been billowing
you must not have been billowing
she must not have been billowing
we must not have been billowing
you must not have been billowing
they must not have been billowing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I billow?
must you billow?
must she billow?
must we billow?
must you billow?
must they billow? 	must I be billowing?
must you be billowing?
must she be billowing?
must we be billowing?
must you be billowing?
must they be billowing? 	must I have billowed?
must you have billowed?
must she have billowed?
must we have billowed?
must you have billowed?
must they have billowed? 	must I have been billowing?
must you have been billowing?
must she have been billowing?
must we have been billowing?
must you have been billowing?
must they have been billowing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not billow?
must you not billow?
must she not billow?
must we not billow?
must you not billow?
must they not billow? 	must I not be billowing?
must you not be billowing?
must she not be billowing?
must we not be billowing?
must you not be billowing?
must they not be billowing? 	must I not have billowed?
must you not have billowed?
must she not have billowed?
must we not have billowed?
must you not have billowed?
must they not have billowed? 	must I not have been billowing?
must you not have been billowing?
must she not have been billowing?
must we not have been billowing?
must you not have been billowing?
must they not have been billowing?