could open
Verbo regular: open - opened- opened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could open
you could open
he could open
we could open
you could open
they could open 	I could be opening
you could be opening
he could be opening
we could be opening
you could be opening
they could be opening	I could have opened
you could have opened
he could have opened
we could have opened
you could have opened
they could have opened	I could have been opening
you could have been opening
he could have been opening
we could have been opening
you could have been opening
they could have been opening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't open
you couldn't open
he couldn't open
we couldn't open
you couldn't open
they couldn't open 	I couldn't be opening
you couldn't be opening
he couldn't be opening
we couldn't be opening
you couldn't be opening
they couldn't be opening	I couldn't have opened
you couldn't have opened
he couldn't have opened
we couldn't have opened
you couldn't have opened
they couldn't have opened	I couldn't have been opening
you couldn't have been opening
he couldn't have been opening
we couldn't have been opening
you couldn't have been opening
they couldn't have been opening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I open?
could you open?
could he open?
could we open?
could you open?
could they open? 	could I be opening?
could you be opening?
could he be opening?
could we be opening?
could you be opening?
could they be opening? 	could I have opened?
could you have opened?
could he have opened?
could we have opened?
could you have opened?
could they have opened? 	could I have been opening?
could you have been opening?
could he have been opening?
could we have been opening?
could you have been opening?
could they have been opening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I open?
couldn't you open?
couldn't he open?
couldn't we open?
couldn't you open?
couldn't they open? 	couldn't I be opening?
couldn't you be opening?
couldn't he be opening?
couldn't we be opening?
couldn't you be opening?
couldn't they be opening? 	couldn't I have opened?
couldn't you have opened?
couldn't he have opened?
couldn't we have opened?
couldn't you have opened?
couldn't they have opened? 	couldn't I have been opening?
couldn't you have been opening?
couldn't he have been opening?
couldn't we have been opening?
couldn't you have been opening?
couldn't they have been opening?