must subtract
Verbo regular: subtract - subtracted- subtracted

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must subtract
you must subtract
he must subtract
we must subtract
you must subtract
they must subtract 	I must be subtracting
you must be subtracting
he must be subtracting
we must be subtracting
you must be subtracting
they must be subtracting	I must have subtracted
you must have subtracted
he must have subtracted
we must have subtracted
you must have subtracted
they must have subtracted	I must have been subtracting
you must have been subtracting
he must have been subtracting
we must have been subtracting
you must have been subtracting
they must have been subtracting	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must not subtract
you must not subtract
he must not subtract
we must not subtract
you must not subtract
they must not subtract 	I must not be subtracting
you must not be subtracting
he must not be subtracting
we must not be subtracting
you must not be subtracting
they must not be subtracting	I must not have subtracted
you must not have subtracted
he must not have subtracted
we must not have subtracted
you must not have subtracted
they must not have subtracted	I must not have been subtracting
you must not have been subtracting
he must not have been subtracting
we must not have been subtracting
you must not have been subtracting
they must not have been subtracting	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I subtract?
must you subtract?
must he subtract?
must we subtract?
must you subtract?
must they subtract? 	must I be subtracting?
must you be subtracting?
must he be subtracting?
must we be subtracting?
must you be subtracting?
must they be subtracting? 	must I have subtracted?
must you have subtracted?
must he have subtracted?
must we have subtracted?
must you have subtracted?
must they have subtracted? 	must I have been subtracting?
must you have been subtracting?
must he have been subtracting?
must we have been subtracting?
must you have been subtracting?
must they have been subtracting? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I not subtract?
must you not subtract?
must he not subtract?
must we not subtract?
must you not subtract?
must they not subtract? 	must I not be subtracting?
must you not be subtracting?
must he not be subtracting?
must we not be subtracting?
must you not be subtracting?
must they not be subtracting? 	must I not have subtracted?
must you not have subtracted?
must he not have subtracted?
must we not have subtracted?
must you not have subtracted?
must they not have subtracted? 	must I not have been subtracting?
must you not have been subtracting?
must he not have been subtracting?
must we not have been subtracting?
must you not have been subtracting?
must they not have been subtracting?