could smoothen
Verbo regular: smoothen - smoothened- smoothened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could smoothen
you could smoothen
he could smoothen
we could smoothen
you could smoothen
they could smoothen 	I could be smoothening
you could be smoothening
he could be smoothening
we could be smoothening
you could be smoothening
they could be smoothening	I could have smoothened
you could have smoothened
he could have smoothened
we could have smoothened
you could have smoothened
they could have smoothened	I could have been smoothening
you could have been smoothening
he could have been smoothening
we could have been smoothening
you could have been smoothening
they could have been smoothening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not smoothen
you could not smoothen
he could not smoothen
we could not smoothen
you could not smoothen
they could not smoothen 	I could not be smoothening
you could not be smoothening
he could not be smoothening
we could not be smoothening
you could not be smoothening
they could not be smoothening	I could not have smoothened
you could not have smoothened
he could not have smoothened
we could not have smoothened
you could not have smoothened
they could not have smoothened	I could not have been smoothening
you could not have been smoothening
he could not have been smoothening
we could not have been smoothening
you could not have been smoothening
they could not have been smoothening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I smoothen?
could you smoothen?
could he smoothen?
could we smoothen?
could you smoothen?
could they smoothen? 	could I be smoothening?
could you be smoothening?
could he be smoothening?
could we be smoothening?
could you be smoothening?
could they be smoothening? 	could I have smoothened?
could you have smoothened?
could he have smoothened?
could we have smoothened?
could you have smoothened?
could they have smoothened? 	could I have been smoothening?
could you have been smoothening?
could he have been smoothening?
could we have been smoothening?
could you have been smoothening?
could they have been smoothening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not smoothen?
could you not smoothen?
could he not smoothen?
could we not smoothen?
could you not smoothen?
could they not smoothen? 	could I not be smoothening?
could you not be smoothening?
could he not be smoothening?
could we not be smoothening?
could you not be smoothening?
could they not be smoothening? 	could I not have smoothened?
could you not have smoothened?
could he not have smoothened?
could we not have smoothened?
could you not have smoothened?
could they not have smoothened? 	could I not have been smoothening?
could you not have been smoothening?
could he not have been smoothening?
could we not have been smoothening?
could you not have been smoothening?
could they not have been smoothening?