could sky
Regular verb: sky - skied- skied

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could sky
you could sky
she could sky
we could sky
you could sky
they could sky 	I could be skying
you could be skying
she could be skying
we could be skying
you could be skying
they could be skying	I could have skied
you could have skied
she could have skied
we could have skied
you could have skied
they could have skied	I could have been skying
you could have been skying
she could have been skying
we could have been skying
you could have been skying
they could have been skying	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't sky
you couldn't sky
she couldn't sky
we couldn't sky
you couldn't sky
they couldn't sky 	I couldn't be skying
you couldn't be skying
she couldn't be skying
we couldn't be skying
you couldn't be skying
they couldn't be skying	I couldn't have skied
you couldn't have skied
she couldn't have skied
we couldn't have skied
you couldn't have skied
they couldn't have skied	I couldn't have been skying
you couldn't have been skying
she couldn't have been skying
we couldn't have been skying
you couldn't have been skying
they couldn't have been skying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I sky?
could you sky?
could she sky?
could we sky?
could you sky?
could they sky? 	could I be skying?
could you be skying?
could she be skying?
could we be skying?
could you be skying?
could they be skying? 	could I have skied?
could you have skied?
could she have skied?
could we have skied?
could you have skied?
could they have skied? 	could I have been skying?
could you have been skying?
could she have been skying?
could we have been skying?
could you have been skying?
could they have been skying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I sky?
couldn't you sky?
couldn't she sky?
couldn't we sky?
couldn't you sky?
couldn't they sky? 	couldn't I be skying?
couldn't you be skying?
couldn't she be skying?
couldn't we be skying?
couldn't you be skying?
couldn't they be skying? 	couldn't I have skied?
couldn't you have skied?
couldn't she have skied?
couldn't we have skied?
couldn't you have skied?
couldn't they have skied? 	couldn't I have been skying?
couldn't you have been skying?
couldn't she have been skying?
couldn't we have been skying?
couldn't you have been skying?
couldn't they have been skying?