must thumbtack
Verbo regular: thumbtack - thumbtacked- thumbtacked

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must thumbtack
you must thumbtack
she must thumbtack
we must thumbtack
you must thumbtack
they must thumbtack 	I must be thumbtacking
you must be thumbtacking
she must be thumbtacking
we must be thumbtacking
you must be thumbtacking
they must be thumbtacking	I must have thumbtacked
you must have thumbtacked
she must have thumbtacked
we must have thumbtacked
you must have thumbtacked
they must have thumbtacked	I must have been thumbtacking
you must have been thumbtacking
she must have been thumbtacking
we must have been thumbtacking
you must have been thumbtacking
they must have been thumbtacking	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must not thumbtack
you must not thumbtack
she must not thumbtack
we must not thumbtack
you must not thumbtack
they must not thumbtack 	I must not be thumbtacking
you must not be thumbtacking
she must not be thumbtacking
we must not be thumbtacking
you must not be thumbtacking
they must not be thumbtacking	I must not have thumbtacked
you must not have thumbtacked
she must not have thumbtacked
we must not have thumbtacked
you must not have thumbtacked
they must not have thumbtacked	I must not have been thumbtacking
you must not have been thumbtacking
she must not have been thumbtacking
we must not have been thumbtacking
you must not have been thumbtacking
they must not have been thumbtacking	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I thumbtack?
must you thumbtack?
must she thumbtack?
must we thumbtack?
must you thumbtack?
must they thumbtack? 	must I be thumbtacking?
must you be thumbtacking?
must she be thumbtacking?
must we be thumbtacking?
must you be thumbtacking?
must they be thumbtacking? 	must I have thumbtacked?
must you have thumbtacked?
must she have thumbtacked?
must we have thumbtacked?
must you have thumbtacked?
must they have thumbtacked? 	must I have been thumbtacking?
must you have been thumbtacking?
must she have been thumbtacking?
must we have been thumbtacking?
must you have been thumbtacking?
must they have been thumbtacking? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I not thumbtack?
must you not thumbtack?
must she not thumbtack?
must we not thumbtack?
must you not thumbtack?
must they not thumbtack? 	must I not be thumbtacking?
must you not be thumbtacking?
must she not be thumbtacking?
must we not be thumbtacking?
must you not be thumbtacking?
must they not be thumbtacking? 	must I not have thumbtacked?
must you not have thumbtacked?
must she not have thumbtacked?
must we not have thumbtacked?
must you not have thumbtacked?
must they not have thumbtacked? 	must I not have been thumbtacking?
must you not have been thumbtacking?
must she not have been thumbtacking?
must we not have been thumbtacking?
must you not have been thumbtacking?
must they not have been thumbtacking?