could ok
Regular verb: ok - oked- oked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could ok
you could ok
she could ok
we could ok
you could ok
they could ok 	I could be oking
you could be oking
she could be oking
we could be oking
you could be oking
they could be oking	I could have oked
you could have oked
she could have oked
we could have oked
you could have oked
they could have oked	I could have been oking
you could have been oking
she could have been oking
we could have been oking
you could have been oking
they could have been oking	

Negation 	
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I couldn't ok
you couldn't ok
she couldn't ok
we couldn't ok
you couldn't ok
they couldn't ok 	I couldn't be oking
you couldn't be oking
she couldn't be oking
we couldn't be oking
you couldn't be oking
they couldn't be oking	I couldn't have oked
you couldn't have oked
she couldn't have oked
we couldn't have oked
you couldn't have oked
they couldn't have oked	I couldn't have been oking
you couldn't have been oking
she couldn't have been oking
we couldn't have been oking
you couldn't have been oking
they couldn't have been oking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I ok?
could you ok?
could she ok?
could we ok?
could you ok?
could they ok? 	could I be oking?
could you be oking?
could she be oking?
could we be oking?
could you be oking?
could they be oking? 	could I have oked?
could you have oked?
could she have oked?
could we have oked?
could you have oked?
could they have oked? 	could I have been oking?
could you have been oking?
could she have been oking?
could we have been oking?
could you have been oking?
could they have been oking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I ok?
couldn't you ok?
couldn't she ok?
couldn't we ok?
couldn't you ok?
couldn't they ok? 	couldn't I be oking?
couldn't you be oking?
couldn't she be oking?
couldn't we be oking?
couldn't you be oking?
couldn't they be oking? 	couldn't I have oked?
couldn't you have oked?
couldn't she have oked?
couldn't we have oked?
couldn't you have oked?
couldn't they have oked? 	couldn't I have been oking?
couldn't you have been oking?
couldn't she have been oking?
couldn't we have been oking?
couldn't you have been oking?
couldn't they have been oking?