may stack
Verbo regular: stack - stacked- stacked

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I may stack
you may stack
she may stack
we may stack
you may stack
they may stack 	I may be stacking
you may be stacking
she may be stacking
we may be stacking
you may be stacking
they may be stacking	I may have stacked
you may have stacked
she may have stacked
we may have stacked
you may have stacked
they may have stacked	I may have been stacking
you may have been stacking
she may have been stacking
we may have been stacking
you may have been stacking
they may have been stacking	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I mayn't stack
you mayn't stack
she mayn't stack
we mayn't stack
you mayn't stack
they mayn't stack 	I mayn't be stacking
you mayn't be stacking
she mayn't be stacking
we mayn't be stacking
you mayn't be stacking
they mayn't be stacking	I mayn't have stacked
you mayn't have stacked
she mayn't have stacked
we mayn't have stacked
you mayn't have stacked
they mayn't have stacked	I mayn't have been stacking
you mayn't have been stacking
she mayn't have been stacking
we mayn't have been stacking
you mayn't have been stacking
they mayn't have been stacking	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
may I stack?
may you stack?
may she stack?
may we stack?
may you stack?
may they stack? 	may I be stacking?
may you be stacking?
may she be stacking?
may we be stacking?
may you be stacking?
may they be stacking? 	may I have stacked?
may you have stacked?
may she have stacked?
may we have stacked?
may you have stacked?
may they have stacked? 	may I have been stacking?
may you have been stacking?
may she have been stacking?
may we have been stacking?
may you have been stacking?
may they have been stacking? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
mayn't I stack?
mayn't you stack?
mayn't she stack?
mayn't we stack?
mayn't you stack?
mayn't they stack? 	mayn't I be stacking?
mayn't you be stacking?
mayn't she be stacking?
mayn't we be stacking?
mayn't you be stacking?
mayn't they be stacking? 	mayn't I have stacked?
mayn't you have stacked?
mayn't she have stacked?
mayn't we have stacked?
mayn't you have stacked?
mayn't they have stacked? 	mayn't I have been stacking?
mayn't you have been stacking?
mayn't she have been stacking?
mayn't we have been stacking?
mayn't you have been stacking?
mayn't they have been stacking?