could nail
Verbo regular: nail - nailed- nailed

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could nail
you could nail
he could nail
we could nail
you could nail
they could nail 	I could be nailing
you could be nailing
he could be nailing
we could be nailing
you could be nailing
they could be nailing	I could have nailed
you could have nailed
he could have nailed
we could have nailed
you could have nailed
they could have nailed	I could have been nailing
you could have been nailing
he could have been nailing
we could have been nailing
you could have been nailing
they could have been nailing	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not nail
you could not nail
he could not nail
we could not nail
you could not nail
they could not nail 	I could not be nailing
you could not be nailing
he could not be nailing
we could not be nailing
you could not be nailing
they could not be nailing	I could not have nailed
you could not have nailed
he could not have nailed
we could not have nailed
you could not have nailed
they could not have nailed	I could not have been nailing
you could not have been nailing
he could not have been nailing
we could not have been nailing
you could not have been nailing
they could not have been nailing	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I nail?
could you nail?
could he nail?
could we nail?
could you nail?
could they nail? 	could I be nailing?
could you be nailing?
could he be nailing?
could we be nailing?
could you be nailing?
could they be nailing? 	could I have nailed?
could you have nailed?
could he have nailed?
could we have nailed?
could you have nailed?
could they have nailed? 	could I have been nailing?
could you have been nailing?
could he have been nailing?
could we have been nailing?
could you have been nailing?
could they have been nailing? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not nail?
could you not nail?
could he not nail?
could we not nail?
could you not nail?
could they not nail? 	could I not be nailing?
could you not be nailing?
could he not be nailing?
could we not be nailing?
could you not be nailing?
could they not be nailing? 	could I not have nailed?
could you not have nailed?
could he not have nailed?
could we not have nailed?
could you not have nailed?
could they not have nailed? 	could I not have been nailing?
could you not have been nailing?
could he not have been nailing?
could we not have been nailing?
could you not have been nailing?
could they not have been nailing?