could perk
Verbo regular: perk - perked- perked

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could perk
you could perk
he could perk
we could perk
you could perk
they could perk 	I could be perking
you could be perking
he could be perking
we could be perking
you could be perking
they could be perking	I could have perked
you could have perked
he could have perked
we could have perked
you could have perked
they could have perked	I could have been perking
you could have been perking
he could have been perking
we could have been perking
you could have been perking
they could have been perking	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not perk
you could not perk
he could not perk
we could not perk
you could not perk
they could not perk 	I could not be perking
you could not be perking
he could not be perking
we could not be perking
you could not be perking
they could not be perking	I could not have perked
you could not have perked
he could not have perked
we could not have perked
you could not have perked
they could not have perked	I could not have been perking
you could not have been perking
he could not have been perking
we could not have been perking
you could not have been perking
they could not have been perking	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I perk?
could you perk?
could he perk?
could we perk?
could you perk?
could they perk? 	could I be perking?
could you be perking?
could he be perking?
could we be perking?
could you be perking?
could they be perking? 	could I have perked?
could you have perked?
could he have perked?
could we have perked?
could you have perked?
could they have perked? 	could I have been perking?
could you have been perking?
could he have been perking?
could we have been perking?
could you have been perking?
could they have been perking? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not perk?
could you not perk?
could he not perk?
could we not perk?
could you not perk?
could they not perk? 	could I not be perking?
could you not be perking?
could he not be perking?
could we not be perking?
could you not be perking?
could they not be perking? 	could I not have perked?
could you not have perked?
could he not have perked?
could we not have perked?
could you not have perked?
could they not have perked? 	could I not have been perking?
could you not have been perking?
could he not have been perking?
could we not have been perking?
could you not have been perking?
could they not have been perking?