could slipper
Verbo regular: slipper - slippered- slippered

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could slipper
you could slipper
he could slipper
we could slipper
you could slipper
they could slipper 	I could be slippering
you could be slippering
he could be slippering
we could be slippering
you could be slippering
they could be slippering	I could have slippered
you could have slippered
he could have slippered
we could have slippered
you could have slippered
they could have slippered	I could have been slippering
you could have been slippering
he could have been slippering
we could have been slippering
you could have been slippering
they could have been slippering	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not slipper
you could not slipper
he could not slipper
we could not slipper
you could not slipper
they could not slipper 	I could not be slippering
you could not be slippering
he could not be slippering
we could not be slippering
you could not be slippering
they could not be slippering	I could not have slippered
you could not have slippered
he could not have slippered
we could not have slippered
you could not have slippered
they could not have slippered	I could not have been slippering
you could not have been slippering
he could not have been slippering
we could not have been slippering
you could not have been slippering
they could not have been slippering	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I slipper?
could you slipper?
could he slipper?
could we slipper?
could you slipper?
could they slipper? 	could I be slippering?
could you be slippering?
could he be slippering?
could we be slippering?
could you be slippering?
could they be slippering? 	could I have slippered?
could you have slippered?
could he have slippered?
could we have slippered?
could you have slippered?
could they have slippered? 	could I have been slippering?
could you have been slippering?
could he have been slippering?
could we have been slippering?
could you have been slippering?
could they have been slippering? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not slipper?
could you not slipper?
could he not slipper?
could we not slipper?
could you not slipper?
could they not slipper? 	could I not be slippering?
could you not be slippering?
could he not be slippering?
could we not be slippering?
could you not be slippering?
could they not be slippering? 	could I not have slippered?
could you not have slippered?
could he not have slippered?
could we not have slippered?
could you not have slippered?
could they not have slippered? 	could I not have been slippering?
could you not have been slippering?
could he not have been slippering?
could we not have been slippering?
could you not have been slippering?
could they not have been slippering?