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 could not yap yap
you could not yap yap
she could not yap yap
we could not yap yap
you could not yap yap
they could not yap yap 	I could not be yap yaping
you could not be yap yaping
she could not be yap yaping
we could not be yap yaping
you could not be yap yaping
they could not be yap yaping	I could not have yap yaped
you could not have yap yaped
she could not have yap yaped
we could not have yap yaped
you could not have yap yaped
they could not have yap yaped	I could not have been yap yaping
you could not have been yap yaping
she could not have been yap yaping
we could not have been yap yaping
you could not have been yap yaping
they could not 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 	
could I not yap yap?
could you not yap yap?
could she not yap yap?
could we not yap yap?
could you not yap yap?
could they not yap yap? 	could I not be yap yaping?
could you not be yap yaping?
could she not be yap yaping?
could we not be yap yaping?
could you not be yap yaping?
could they not be yap yaping? 	could I not have yap yaped?
could you not have yap yaped?
could she not have yap yaped?
could we not have yap yaped?
could you not have yap yaped?
could they not have yap yaped? 	could I not have been yap yaping?
could you not have been yap yaping?
could she not have been yap yaping?
could we not have been yap yaping?
could you not have been yap yaping?
could they not have been yap yaping?