must fib
Verbo regular: fib - fibbed- fibbed

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must fib
you must fib
he must fib
we must fib
you must fib
they must fib 	I must be fibbing
you must be fibbing
he must be fibbing
we must be fibbing
you must be fibbing
they must be fibbing	I must have fibbed
you must have fibbed
he must have fibbed
we must have fibbed
you must have fibbed
they must have fibbed	I must have been fibbing
you must have been fibbing
he must have been fibbing
we must have been fibbing
you must have been fibbing
they must have been fibbing	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must not fib
you must not fib
he must not fib
we must not fib
you must not fib
they must not fib 	I must not be fibbing
you must not be fibbing
he must not be fibbing
we must not be fibbing
you must not be fibbing
they must not be fibbing	I must not have fibbed
you must not have fibbed
he must not have fibbed
we must not have fibbed
you must not have fibbed
they must not have fibbed	I must not have been fibbing
you must not have been fibbing
he must not have been fibbing
we must not have been fibbing
you must not have been fibbing
they must not have been fibbing	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I fib?
must you fib?
must he fib?
must we fib?
must you fib?
must they fib? 	must I be fibbing?
must you be fibbing?
must he be fibbing?
must we be fibbing?
must you be fibbing?
must they be fibbing? 	must I have fibbed?
must you have fibbed?
must he have fibbed?
must we have fibbed?
must you have fibbed?
must they have fibbed? 	must I have been fibbing?
must you have been fibbing?
must he have been fibbing?
must we have been fibbing?
must you have been fibbing?
must they have been fibbing? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I not fib?
must you not fib?
must he not fib?
must we not fib?
must you not fib?
must they not fib? 	must I not be fibbing?
must you not be fibbing?
must he not be fibbing?
must we not be fibbing?
must you not be fibbing?
must they not be fibbing? 	must I not have fibbed?
must you not have fibbed?
must he not have fibbed?
must we not have fibbed?
must you not have fibbed?
must they not have fibbed? 	must I not have been fibbing?
must you not have been fibbing?
must he not have been fibbing?
must we not have been fibbing?
must you not have been fibbing?
must they not have been fibbing?