could stone
Verbo regular: stone - stoned- stoned

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could stone
you could stone
he could stone
we could stone
you could stone
they could stone 	I could be stoning
you could be stoning
he could be stoning
we could be stoning
you could be stoning
they could be stoning	I could have stoned
you could have stoned
he could have stoned
we could have stoned
you could have stoned
they could have stoned	I could have been stoning
you could have been stoning
he could have been stoning
we could have been stoning
you could have been stoning
they could have been stoning	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't stone
you couldn't stone
he couldn't stone
we couldn't stone
you couldn't stone
they couldn't stone 	I couldn't be stoning
you couldn't be stoning
he couldn't be stoning
we couldn't be stoning
you couldn't be stoning
they couldn't be stoning	I couldn't have stoned
you couldn't have stoned
he couldn't have stoned
we couldn't have stoned
you couldn't have stoned
they couldn't have stoned	I couldn't have been stoning
you couldn't have been stoning
he couldn't have been stoning
we couldn't have been stoning
you couldn't have been stoning
they couldn't have been stoning	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I stone?
could you stone?
could he stone?
could we stone?
could you stone?
could they stone? 	could I be stoning?
could you be stoning?
could he be stoning?
could we be stoning?
could you be stoning?
could they be stoning? 	could I have stoned?
could you have stoned?
could he have stoned?
could we have stoned?
could you have stoned?
could they have stoned? 	could I have been stoning?
could you have been stoning?
could he have been stoning?
could we have been stoning?
could you have been stoning?
could they have been stoning? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I stone?
couldn't you stone?
couldn't he stone?
couldn't we stone?
couldn't you stone?
couldn't they stone? 	couldn't I be stoning?
couldn't you be stoning?
couldn't he be stoning?
couldn't we be stoning?
couldn't you be stoning?
couldn't they be stoning? 	couldn't I have stoned?
couldn't you have stoned?
couldn't he have stoned?
couldn't we have stoned?
couldn't you have stoned?
couldn't they have stoned? 	couldn't I have been stoning?
couldn't you have been stoning?
couldn't he have been stoning?
couldn't we have been stoning?
couldn't you have been stoning?
couldn't they have been stoning?