could yip
Regular verb: yip - yipped- yipped

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could yip
you could yip
she could yip
we could yip
you could yip
they could yip 	I could be yipping
you could be yipping
she could be yipping
we could be yipping
you could be yipping
they could be yipping	I could have yipped
you could have yipped
she could have yipped
we could have yipped
you could have yipped
they could have yipped	I could have been yipping
you could have been yipping
she could have been yipping
we could have been yipping
you could have been yipping
they could have been yipping	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't yip
you couldn't yip
she couldn't yip
we couldn't yip
you couldn't yip
they couldn't yip 	I couldn't be yipping
you couldn't be yipping
she couldn't be yipping
we couldn't be yipping
you couldn't be yipping
they couldn't be yipping	I couldn't have yipped
you couldn't have yipped
she couldn't have yipped
we couldn't have yipped
you couldn't have yipped
they couldn't have yipped	I couldn't have been yipping
you couldn't have been yipping
she couldn't have been yipping
we couldn't have been yipping
you couldn't have been yipping
they couldn't have been yipping	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I yip?
could you yip?
could she yip?
could we yip?
could you yip?
could they yip? 	could I be yipping?
could you be yipping?
could she be yipping?
could we be yipping?
could you be yipping?
could they be yipping? 	could I have yipped?
could you have yipped?
could she have yipped?
could we have yipped?
could you have yipped?
could they have yipped? 	could I have been yipping?
could you have been yipping?
could she have been yipping?
could we have been yipping?
could you have been yipping?
could they have been yipping? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I yip?
couldn't you yip?
couldn't she yip?
couldn't we yip?
couldn't you yip?
couldn't they yip? 	couldn't I be yipping?
couldn't you be yipping?
couldn't she be yipping?
couldn't we be yipping?
couldn't you be yipping?
couldn't they be yipping? 	couldn't I have yipped?
couldn't you have yipped?
couldn't she have yipped?
couldn't we have yipped?
couldn't you have yipped?
couldn't they have yipped? 	couldn't I have been yipping?
couldn't you have been yipping?
couldn't she have been yipping?
couldn't we have been yipping?
couldn't you have been yipping?
couldn't they have been yipping?