could pin
Verbo regular: pin - pinned- pinned

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could pin
you could pin
he could pin
we could pin
you could pin
they could pin 	I could be pinning
you could be pinning
he could be pinning
we could be pinning
you could be pinning
they could be pinning	I could have pinned
you could have pinned
he could have pinned
we could have pinned
you could have pinned
they could have pinned	I could have been pinning
you could have been pinning
he could have been pinning
we could have been pinning
you could have been pinning
they could have been pinning	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I couldn't pin
you couldn't pin
he couldn't pin
we couldn't pin
you couldn't pin
they couldn't pin 	I couldn't be pinning
you couldn't be pinning
he couldn't be pinning
we couldn't be pinning
you couldn't be pinning
they couldn't be pinning	I couldn't have pinned
you couldn't have pinned
he couldn't have pinned
we couldn't have pinned
you couldn't have pinned
they couldn't have pinned	I couldn't have been pinning
you couldn't have been pinning
he couldn't have been pinning
we couldn't have been pinning
you couldn't have been pinning
they couldn't have been pinning	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I pin?
could you pin?
could he pin?
could we pin?
could you pin?
could they pin? 	could I be pinning?
could you be pinning?
could he be pinning?
could we be pinning?
could you be pinning?
could they be pinning? 	could I have pinned?
could you have pinned?
could he have pinned?
could we have pinned?
could you have pinned?
could they have pinned? 	could I have been pinning?
could you have been pinning?
could he have been pinning?
could we have been pinning?
could you have been pinning?
could they have been pinning? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
couldn't I pin?
couldn't you pin?
couldn't he pin?
couldn't we pin?
couldn't you pin?
couldn't they pin? 	couldn't I be pinning?
couldn't you be pinning?
couldn't he be pinning?
couldn't we be pinning?
couldn't you be pinning?
couldn't they be pinning? 	couldn't I have pinned?
couldn't you have pinned?
couldn't he have pinned?
couldn't we have pinned?
couldn't you have pinned?
couldn't they have pinned? 	couldn't I have been pinning?
couldn't you have been pinning?
couldn't he have been pinning?
couldn't we have been pinning?
couldn't you have been pinning?
couldn't they have been pinning?