could yap yap
Regular verb: yap yap - yap yaped- yap yaped

, this verb may not exist. Conjugation is given as example.

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could yap yap
you could yap yap
she could yap yap
we could yap yap
you could yap yap
they could yap yap 	I could be yap yaping
you could be yap yaping
she could be yap yaping
we could be yap yaping
you could be yap yaping
they could be yap yaping	I could have yap yaped
you could have yap yaped
she could have yap yaped
we could have yap yaped
you could have yap yaped
they could have yap yaped	I could have been yap yaping
you could have been yap yaping
she could have been yap yaping
we could have been yap yaping
you could have been yap yaping
they could have been yap yaping	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't yap yap
you couldn't yap yap
she couldn't yap yap
we couldn't yap yap
you couldn't yap yap
they couldn't yap yap 	I couldn't be yap yaping
you couldn't be yap yaping
she couldn't be yap yaping
we couldn't be yap yaping
you couldn't be yap yaping
they couldn't be yap yaping	I couldn't have yap yaped
you couldn't have yap yaped
she couldn't have yap yaped
we couldn't have yap yaped
you couldn't have yap yaped
they couldn't have yap yaped	I couldn't have been yap yaping
you couldn't have been yap yaping
she couldn't have been yap yaping
we couldn't have been yap yaping
you couldn't have been yap yaping
they couldn't have been yap yaping	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I yap yap?
could you yap yap?
could she yap yap?
could we yap yap?
could you yap yap?
could they yap yap? 	could I be yap yaping?
could you be yap yaping?
could she be yap yaping?
could we be yap yaping?
could you be yap yaping?
could they be yap yaping? 	could I have yap yaped?
could you have yap yaped?
could she have yap yaped?
could we have yap yaped?
could you have yap yaped?
could they have yap yaped? 	could I have been yap yaping?
could you have been yap yaping?
could she have been yap yaping?
could we have been yap yaping?
could you have been yap yaping?
could they have been yap yaping? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I yap yap?
couldn't you yap yap?
couldn't she yap yap?
couldn't we yap yap?
couldn't you yap yap?
couldn't they yap yap? 	couldn't I be yap yaping?
couldn't you be yap yaping?
couldn't she be yap yaping?
couldn't we be yap yaping?
couldn't you be yap yaping?
couldn't they be yap yaping? 	couldn't I have yap yaped?
couldn't you have yap yaped?
couldn't she have yap yaped?
couldn't we have yap yaped?
couldn't you have yap yaped?
couldn't they have yap yaped? 	couldn't I have been yap yaping?
couldn't you have been yap yaping?
couldn't she have been yap yaping?
couldn't we have been yap yaping?
couldn't you have been yap yaping?
couldn't they have been yap yaping?