must lessen
Verbo regular: lessen - lessened- lessened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must lessen
you must lessen
he must lessen
we must lessen
you must lessen
they must lessen 	I must be lessening
you must be lessening
he must be lessening
we must be lessening
you must be lessening
they must be lessening	I must have lessened
you must have lessened
he must have lessened
we must have lessened
you must have lessened
they must have lessened	I must have been lessening
you must have been lessening
he must have been lessening
we must have been lessening
you must have been lessening
they must have been lessening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must not lessen
you must not lessen
he must not lessen
we must not lessen
you must not lessen
they must not lessen 	I must not be lessening
you must not be lessening
he must not be lessening
we must not be lessening
you must not be lessening
they must not be lessening	I must not have lessened
you must not have lessened
he must not have lessened
we must not have lessened
you must not have lessened
they must not have lessened	I must not have been lessening
you must not have been lessening
he must not have been lessening
we must not have been lessening
you must not have been lessening
they must not have been lessening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I lessen?
must you lessen?
must he lessen?
must we lessen?
must you lessen?
must they lessen? 	must I be lessening?
must you be lessening?
must he be lessening?
must we be lessening?
must you be lessening?
must they be lessening? 	must I have lessened?
must you have lessened?
must he have lessened?
must we have lessened?
must you have lessened?
must they have lessened? 	must I have been lessening?
must you have been lessening?
must he have been lessening?
must we have been lessening?
must you have been lessening?
must they have been lessening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I not lessen?
must you not lessen?
must he not lessen?
must we not lessen?
must you not lessen?
must they not lessen? 	must I not be lessening?
must you not be lessening?
must he not be lessening?
must we not be lessening?
must you not be lessening?
must they not be lessening? 	must I not have lessened?
must you not have lessened?
must he not have lessened?
must we not have lessened?
must you not have lessened?
must they not have lessened? 	must I not have been lessening?
must you not have been lessening?
must he not have been lessening?
must we not have been lessening?
must you not have been lessening?
must they not have been lessening?