must collapse
Verbo regular: collapse - collapsed- collapsed

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must collapse
you must collapse
he must collapse
we must collapse
you must collapse
they must collapse 	I must be collapsing
you must be collapsing
he must be collapsing
we must be collapsing
you must be collapsing
they must be collapsing	I must have collapsed
you must have collapsed
he must have collapsed
we must have collapsed
you must have collapsed
they must have collapsed	I must have been collapsing
you must have been collapsing
he must have been collapsing
we must have been collapsing
you must have been collapsing
they must have been collapsing	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must not collapse
you must not collapse
he must not collapse
we must not collapse
you must not collapse
they must not collapse 	I must not be collapsing
you must not be collapsing
he must not be collapsing
we must not be collapsing
you must not be collapsing
they must not be collapsing	I must not have collapsed
you must not have collapsed
he must not have collapsed
we must not have collapsed
you must not have collapsed
they must not have collapsed	I must not have been collapsing
you must not have been collapsing
he must not have been collapsing
we must not have been collapsing
you must not have been collapsing
they must not have been collapsing	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I collapse?
must you collapse?
must he collapse?
must we collapse?
must you collapse?
must they collapse? 	must I be collapsing?
must you be collapsing?
must he be collapsing?
must we be collapsing?
must you be collapsing?
must they be collapsing? 	must I have collapsed?
must you have collapsed?
must he have collapsed?
must we have collapsed?
must you have collapsed?
must they have collapsed? 	must I have been collapsing?
must you have been collapsing?
must he have been collapsing?
must we have been collapsing?
must you have been collapsing?
must they have been collapsing? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I not collapse?
must you not collapse?
must he not collapse?
must we not collapse?
must you not collapse?
must they not collapse? 	must I not be collapsing?
must you not be collapsing?
must he not be collapsing?
must we not be collapsing?
must you not be collapsing?
must they not be collapsing? 	must I not have collapsed?
must you not have collapsed?
must he not have collapsed?
must we not have collapsed?
must you not have collapsed?
must they not have collapsed? 	must I not have been collapsing?
must you not have been collapsing?
must he not have been collapsing?
must we not have been collapsing?
must you not have been collapsing?
must they not have been collapsing?