could curtain
Verbo regular: curtain - curtained- curtained

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could curtain
you could curtain
he could curtain
we could curtain
you could curtain
they could curtain 	I could be curtaining
you could be curtaining
he could be curtaining
we could be curtaining
you could be curtaining
they could be curtaining	I could have curtained
you could have curtained
he could have curtained
we could have curtained
you could have curtained
they could have curtained	I could have been curtaining
you could have been curtaining
he could have been curtaining
we could have been curtaining
you could have been curtaining
they could have been curtaining	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't curtain
you couldn't curtain
he couldn't curtain
we couldn't curtain
you couldn't curtain
they couldn't curtain 	I couldn't be curtaining
you couldn't be curtaining
he couldn't be curtaining
we couldn't be curtaining
you couldn't be curtaining
they couldn't be curtaining	I couldn't have curtained
you couldn't have curtained
he couldn't have curtained
we couldn't have curtained
you couldn't have curtained
they couldn't have curtained	I couldn't have been curtaining
you couldn't have been curtaining
he couldn't have been curtaining
we couldn't have been curtaining
you couldn't have been curtaining
they couldn't have been curtaining	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I curtain?
could you curtain?
could he curtain?
could we curtain?
could you curtain?
could they curtain? 	could I be curtaining?
could you be curtaining?
could he be curtaining?
could we be curtaining?
could you be curtaining?
could they be curtaining? 	could I have curtained?
could you have curtained?
could he have curtained?
could we have curtained?
could you have curtained?
could they have curtained? 	could I have been curtaining?
could you have been curtaining?
could he have been curtaining?
could we have been curtaining?
could you have been curtaining?
could they have been curtaining? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I curtain?
couldn't you curtain?
couldn't he curtain?
couldn't we curtain?
couldn't you curtain?
couldn't they curtain? 	couldn't I be curtaining?
couldn't you be curtaining?
couldn't he be curtaining?
couldn't we be curtaining?
couldn't you be curtaining?
couldn't they be curtaining? 	couldn't I have curtained?
couldn't you have curtained?
couldn't he have curtained?
couldn't we have curtained?
couldn't you have curtained?
couldn't they have curtained? 	couldn't I have been curtaining?
couldn't you have been curtaining?
couldn't he have been curtaining?
couldn't we have been curtaining?
couldn't you have been curtaining?
couldn't they have been curtaining?