could yell
Verbo regular: yell - yelled- yelled

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could yell
you could yell
he could yell
we could yell
you could yell
they could yell 	I could be yelling
you could be yelling
he could be yelling
we could be yelling
you could be yelling
they could be yelling	I could have yelled
you could have yelled
he could have yelled
we could have yelled
you could have yelled
they could have yelled	I could have been yelling
you could have been yelling
he could have been yelling
we could have been yelling
you could have been yelling
they could have been yelling	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not yell
you could not yell
he could not yell
we could not yell
you could not yell
they could not yell 	I could not be yelling
you could not be yelling
he could not be yelling
we could not be yelling
you could not be yelling
they could not be yelling	I could not have yelled
you could not have yelled
he could not have yelled
we could not have yelled
you could not have yelled
they could not have yelled	I could not have been yelling
you could not have been yelling
he could not have been yelling
we could not have been yelling
you could not have been yelling
they could not have been yelling	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I yell?
could you yell?
could he yell?
could we yell?
could you yell?
could they yell? 	could I be yelling?
could you be yelling?
could he be yelling?
could we be yelling?
could you be yelling?
could they be yelling? 	could I have yelled?
could you have yelled?
could he have yelled?
could we have yelled?
could you have yelled?
could they have yelled? 	could I have been yelling?
could you have been yelling?
could he have been yelling?
could we have been yelling?
could you have been yelling?
could they have been yelling? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not yell?
could you not yell?
could he not yell?
could we not yell?
could you not yell?
could they not yell? 	could I not be yelling?
could you not be yelling?
could he not be yelling?
could we not be yelling?
could you not be yelling?
could they not be yelling? 	could I not have yelled?
could you not have yelled?
could he not have yelled?
could we not have yelled?
could you not have yelled?
could they not have yelled? 	could I not have been yelling?
could you not have been yelling?
could he not have been yelling?
could we not have been yelling?
could you not have been yelling?
could they not have been yelling?