could mutter
Verbo regular: mutter - muttered- muttered

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could mutter
you could mutter
he could mutter
we could mutter
you could mutter
they could mutter 	I could be muttering
you could be muttering
he could be muttering
we could be muttering
you could be muttering
they could be muttering	I could have muttered
you could have muttered
he could have muttered
we could have muttered
you could have muttered
they could have muttered	I could have been muttering
you could have been muttering
he could have been muttering
we could have been muttering
you could have been muttering
they could have been muttering	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not mutter
you could not mutter
he could not mutter
we could not mutter
you could not mutter
they could not mutter 	I could not be muttering
you could not be muttering
he could not be muttering
we could not be muttering
you could not be muttering
they could not be muttering	I could not have muttered
you could not have muttered
he could not have muttered
we could not have muttered
you could not have muttered
they could not have muttered	I could not have been muttering
you could not have been muttering
he could not have been muttering
we could not have been muttering
you could not have been muttering
they could not have been muttering	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I mutter?
could you mutter?
could he mutter?
could we mutter?
could you mutter?
could they mutter? 	could I be muttering?
could you be muttering?
could he be muttering?
could we be muttering?
could you be muttering?
could they be muttering? 	could I have muttered?
could you have muttered?
could he have muttered?
could we have muttered?
could you have muttered?
could they have muttered? 	could I have been muttering?
could you have been muttering?
could he have been muttering?
could we have been muttering?
could you have been muttering?
could they have been muttering? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not mutter?
could you not mutter?
could he not mutter?
could we not mutter?
could you not mutter?
could they not mutter? 	could I not be muttering?
could you not be muttering?
could he not be muttering?
could we not be muttering?
could you not be muttering?
could they not be muttering? 	could I not have muttered?
could you not have muttered?
could he not have muttered?
could we not have muttered?
could you not have muttered?
could they not have muttered? 	could I not have been muttering?
could you not have been muttering?
could he not have been muttering?
could we not have been muttering?
could you not have been muttering?
could they not have been muttering?