could ski
Verbo regular: ski - skied- skied

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could ski
you could ski
he could ski
we could ski
you could ski
they could ski 	I could be skiing
you could be skiing
he could be skiing
we could be skiing
you could be skiing
they could be skiing	I could have skied
you could have skied
he could have skied
we could have skied
you could have skied
they could have skied	I could have been skiing
you could have been skiing
he could have been skiing
we could have been skiing
you could have been skiing
they could have been skiing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not ski
you could not ski
he could not ski
we could not ski
you could not ski
they could not ski 	I could not be skiing
you could not be skiing
he could not be skiing
we could not be skiing
you could not be skiing
they could not be skiing	I could not have skied
you could not have skied
he could not have skied
we could not have skied
you could not have skied
they could not have skied	I could not have been skiing
you could not have been skiing
he could not have been skiing
we could not have been skiing
you could not have been skiing
they could not have been skiing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I ski?
could you ski?
could he ski?
could we ski?
could you ski?
could they ski? 	could I be skiing?
could you be skiing?
could he be skiing?
could we be skiing?
could you be skiing?
could they be skiing? 	could I have skied?
could you have skied?
could he have skied?
could we have skied?
could you have skied?
could they have skied? 	could I have been skiing?
could you have been skiing?
could he have been skiing?
could we have been skiing?
could you have been skiing?
could they have been skiing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not ski?
could you not ski?
could he not ski?
could we not ski?
could you not ski?
could they not ski? 	could I not be skiing?
could you not be skiing?
could he not be skiing?
could we not be skiing?
could you not be skiing?
could they not be skiing? 	could I not have skied?
could you not have skied?
could he not have skied?
could we not have skied?
could you not have skied?
could they not have skied? 	could I not have been skiing?
could you not have been skiing?
could he not have been skiing?
could we not have been skiing?
could you not have been skiing?
could they not have been skiing?