could sail
Verbo regular: sail - sailed- sailed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could sail
you could sail
he could sail
we could sail
you could sail
they could sail 	I could be sailing
you could be sailing
he could be sailing
we could be sailing
you could be sailing
they could be sailing	I could have sailed
you could have sailed
he could have sailed
we could have sailed
you could have sailed
they could have sailed	I could have been sailing
you could have been sailing
he could have been sailing
we could have been sailing
you could have been sailing
they could have been sailing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't sail
you couldn't sail
he couldn't sail
we couldn't sail
you couldn't sail
they couldn't sail 	I couldn't be sailing
you couldn't be sailing
he couldn't be sailing
we couldn't be sailing
you couldn't be sailing
they couldn't be sailing	I couldn't have sailed
you couldn't have sailed
he couldn't have sailed
we couldn't have sailed
you couldn't have sailed
they couldn't have sailed	I couldn't have been sailing
you couldn't have been sailing
he couldn't have been sailing
we couldn't have been sailing
you couldn't have been sailing
they couldn't have been sailing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I sail?
could you sail?
could he sail?
could we sail?
could you sail?
could they sail? 	could I be sailing?
could you be sailing?
could he be sailing?
could we be sailing?
could you be sailing?
could they be sailing? 	could I have sailed?
could you have sailed?
could he have sailed?
could we have sailed?
could you have sailed?
could they have sailed? 	could I have been sailing?
could you have been sailing?
could he have been sailing?
could we have been sailing?
could you have been sailing?
could they have been sailing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I sail?
couldn't you sail?
couldn't he sail?
couldn't we sail?
couldn't you sail?
couldn't they sail? 	couldn't I be sailing?
couldn't you be sailing?
couldn't he be sailing?
couldn't we be sailing?
couldn't you be sailing?
couldn't they be sailing? 	couldn't I have sailed?
couldn't you have sailed?
couldn't he have sailed?
couldn't we have sailed?
couldn't you have sailed?
couldn't they have sailed? 	couldn't I have been sailing?
couldn't you have been sailing?
couldn't he have been sailing?
couldn't we have been sailing?
couldn't you have been sailing?
couldn't they have been sailing?