may stiffen
Verbo regular: stiffen - stiffened- stiffened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I may stiffen
you may stiffen
he may stiffen
we may stiffen
you may stiffen
they may stiffen 	I may be stiffening
you may be stiffening
he may be stiffening
we may be stiffening
you may be stiffening
they may be stiffening	I may have stiffened
you may have stiffened
he may have stiffened
we may have stiffened
you may have stiffened
they may have stiffened	I may have been stiffening
you may have been stiffening
he may have been stiffening
we may have been stiffening
you may have been stiffening
they may have been stiffening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I mayn't stiffen
you mayn't stiffen
he mayn't stiffen
we mayn't stiffen
you mayn't stiffen
they mayn't stiffen 	I mayn't be stiffening
you mayn't be stiffening
he mayn't be stiffening
we mayn't be stiffening
you mayn't be stiffening
they mayn't be stiffening	I mayn't have stiffened
you mayn't have stiffened
he mayn't have stiffened
we mayn't have stiffened
you mayn't have stiffened
they mayn't have stiffened	I mayn't have been stiffening
you mayn't have been stiffening
he mayn't have been stiffening
we mayn't have been stiffening
you mayn't have been stiffening
they mayn't have been stiffening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
may I stiffen?
may you stiffen?
may he stiffen?
may we stiffen?
may you stiffen?
may they stiffen? 	may I be stiffening?
may you be stiffening?
may he be stiffening?
may we be stiffening?
may you be stiffening?
may they be stiffening? 	may I have stiffened?
may you have stiffened?
may he have stiffened?
may we have stiffened?
may you have stiffened?
may they have stiffened? 	may I have been stiffening?
may you have been stiffening?
may he have been stiffening?
may we have been stiffening?
may you have been stiffening?
may they have been stiffening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
mayn't I stiffen?
mayn't you stiffen?
mayn't he stiffen?
mayn't we stiffen?
mayn't you stiffen?
mayn't they stiffen? 	mayn't I be stiffening?
mayn't you be stiffening?
mayn't he be stiffening?
mayn't we be stiffening?
mayn't you be stiffening?
mayn't they be stiffening? 	mayn't I have stiffened?
mayn't you have stiffened?
mayn't he have stiffened?
mayn't we have stiffened?
mayn't you have stiffened?
mayn't they have stiffened? 	mayn't I have been stiffening?
mayn't you have been stiffening?
mayn't he have been stiffening?
mayn't we have been stiffening?
mayn't you have been stiffening?
mayn't they have been stiffening?