could yuk
Regular verb: yuk - yuked- yuked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could yuk
you could yuk
she could yuk
we could yuk
you could yuk
they could yuk 	I could be yuking
you could be yuking
she could be yuking
we could be yuking
you could be yuking
they could be yuking	I could have yuked
you could have yuked
she could have yuked
we could have yuked
you could have yuked
they could have yuked	I could have been yuking
you could have been yuking
she could have been yuking
we could have been yuking
you could have been yuking
they could have been yuking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't yuk
you couldn't yuk
she couldn't yuk
we couldn't yuk
you couldn't yuk
they couldn't yuk 	I couldn't be yuking
you couldn't be yuking
she couldn't be yuking
we couldn't be yuking
you couldn't be yuking
they couldn't be yuking	I couldn't have yuked
you couldn't have yuked
she couldn't have yuked
we couldn't have yuked
you couldn't have yuked
they couldn't have yuked	I couldn't have been yuking
you couldn't have been yuking
she couldn't have been yuking
we couldn't have been yuking
you couldn't have been yuking
they couldn't have been yuking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I yuk?
could you yuk?
could she yuk?
could we yuk?
could you yuk?
could they yuk? 	could I be yuking?
could you be yuking?
could she be yuking?
could we be yuking?
could you be yuking?
could they be yuking? 	could I have yuked?
could you have yuked?
could she have yuked?
could we have yuked?
could you have yuked?
could they have yuked? 	could I have been yuking?
could you have been yuking?
could she have been yuking?
could we have been yuking?
could you have been yuking?
could they have been yuking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I yuk?
couldn't you yuk?
couldn't she yuk?
couldn't we yuk?
couldn't you yuk?
couldn't they yuk? 	couldn't I be yuking?
couldn't you be yuking?
couldn't she be yuking?
couldn't we be yuking?
couldn't you be yuking?
couldn't they be yuking? 	couldn't I have yuked?
couldn't you have yuked?
couldn't she have yuked?
couldn't we have yuked?
couldn't you have yuked?
couldn't they have yuked? 	couldn't I have been yuking?
couldn't you have been yuking?
couldn't she have been yuking?
couldn't we have been yuking?
couldn't you have been yuking?
couldn't they have been yuking?