could perturb
Verbo regular: perturb - perturbed- perturbed

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could perturb
you could perturb
he could perturb
we could perturb
you could perturb
they could perturb 	I could be perturbing
you could be perturbing
he could be perturbing
we could be perturbing
you could be perturbing
they could be perturbing	I could have perturbed
you could have perturbed
he could have perturbed
we could have perturbed
you could have perturbed
they could have perturbed	I could have been perturbing
you could have been perturbing
he could have been perturbing
we could have been perturbing
you could have been perturbing
they could have been perturbing	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not perturb
you could not perturb
he could not perturb
we could not perturb
you could not perturb
they could not perturb 	I could not be perturbing
you could not be perturbing
he could not be perturbing
we could not be perturbing
you could not be perturbing
they could not be perturbing	I could not have perturbed
you could not have perturbed
he could not have perturbed
we could not have perturbed
you could not have perturbed
they could not have perturbed	I could not have been perturbing
you could not have been perturbing
he could not have been perturbing
we could not have been perturbing
you could not have been perturbing
they could not have been perturbing	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I perturb?
could you perturb?
could he perturb?
could we perturb?
could you perturb?
could they perturb? 	could I be perturbing?
could you be perturbing?
could he be perturbing?
could we be perturbing?
could you be perturbing?
could they be perturbing? 	could I have perturbed?
could you have perturbed?
could he have perturbed?
could we have perturbed?
could you have perturbed?
could they have perturbed? 	could I have been perturbing?
could you have been perturbing?
could he have been perturbing?
could we have been perturbing?
could you have been perturbing?
could they have been perturbing? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not perturb?
could you not perturb?
could he not perturb?
could we not perturb?
could you not perturb?
could they not perturb? 	could I not be perturbing?
could you not be perturbing?
could he not be perturbing?
could we not be perturbing?
could you not be perturbing?
could they not be perturbing? 	could I not have perturbed?
could you not have perturbed?
could he not have perturbed?
could we not have perturbed?
could you not have perturbed?
could they not have perturbed? 	could I not have been perturbing?
could you not have been perturbing?
could he not have been perturbing?
could we not have been perturbing?
could you not have been perturbing?
could they not have been perturbing?