must piffle
Regular verb: piffle - piffled- piffled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must piffle
you must piffle
he must piffle
we must piffle
you must piffle
they must piffle 	I must be piffling
you must be piffling
he must be piffling
we must be piffling
you must be piffling
they must be piffling	I must have piffled
you must have piffled
he must have piffled
we must have piffled
you must have piffled
they must have piffled	I must have been piffling
you must have been piffling
he must have been piffling
we must have been piffling
you must have been piffling
they must have been piffling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not piffle
you must not piffle
he must not piffle
we must not piffle
you must not piffle
they must not piffle 	I must not be piffling
you must not be piffling
he must not be piffling
we must not be piffling
you must not be piffling
they must not be piffling	I must not have piffled
you must not have piffled
he must not have piffled
we must not have piffled
you must not have piffled
they must not have piffled	I must not have been piffling
you must not have been piffling
he must not have been piffling
we must not have been piffling
you must not have been piffling
they must not have been piffling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I piffle?
must you piffle?
must he piffle?
must we piffle?
must you piffle?
must they piffle? 	must I be piffling?
must you be piffling?
must he be piffling?
must we be piffling?
must you be piffling?
must they be piffling? 	must I have piffled?
must you have piffled?
must he have piffled?
must we have piffled?
must you have piffled?
must they have piffled? 	must I have been piffling?
must you have been piffling?
must he have been piffling?
must we have been piffling?
must you have been piffling?
must they have been piffling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not piffle?
must you not piffle?
must he not piffle?
must we not piffle?
must you not piffle?
must they not piffle? 	must I not be piffling?
must you not be piffling?
must he not be piffling?
must we not be piffling?
must you not be piffling?
must they not be piffling? 	must I not have piffled?
must you not have piffled?
must he not have piffled?
must we not have piffled?
must you not have piffled?
must they not have piffled? 	must I not have been piffling?
must you not have been piffling?
must he not have been piffling?
must we not have been piffling?
must you not have been piffling?
must they not have been piffling?