could birl
Verbo regular: birl - birled- birled

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could birl
you could birl
he could birl
we could birl
you could birl
they could birl 	I could be birling
you could be birling
he could be birling
we could be birling
you could be birling
they could be birling	I could have birled
you could have birled
he could have birled
we could have birled
you could have birled
they could have birled	I could have been birling
you could have been birling
he could have been birling
we could have been birling
you could have been birling
they could have been birling	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not birl
you could not birl
he could not birl
we could not birl
you could not birl
they could not birl 	I could not be birling
you could not be birling
he could not be birling
we could not be birling
you could not be birling
they could not be birling	I could not have birled
you could not have birled
he could not have birled
we could not have birled
you could not have birled
they could not have birled	I could not have been birling
you could not have been birling
he could not have been birling
we could not have been birling
you could not have been birling
they could not have been birling	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I birl?
could you birl?
could he birl?
could we birl?
could you birl?
could they birl? 	could I be birling?
could you be birling?
could he be birling?
could we be birling?
could you be birling?
could they be birling? 	could I have birled?
could you have birled?
could he have birled?
could we have birled?
could you have birled?
could they have birled? 	could I have been birling?
could you have been birling?
could he have been birling?
could we have been birling?
could you have been birling?
could they have been birling? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not birl?
could you not birl?
could he not birl?
could we not birl?
could you not birl?
could they not birl? 	could I not be birling?
could you not be birling?
could he not be birling?
could we not be birling?
could you not be birling?
could they not be birling? 	could I not have birled?
could you not have birled?
could he not have birled?
could we not have birled?
could you not have birled?
could they not have birled? 	could I not have been birling?
could you not have been birling?
could he not have been birling?
could we not have been birling?
could you not have been birling?
could they not have been birling?