could yackety-yack
Verbe régulier : yackety-yack - yackety-yacked- yackety-yacked

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could yackety-yack
you could yackety-yack
he could yackety-yack
we could yackety-yack
you could yackety-yack
they could yackety-yack 	I could be yackety-yacking
you could be yackety-yacking
he could be yackety-yacking
we could be yackety-yacking
you could be yackety-yacking
they could be yackety-yacking	I could have yackety-yacked
you could have yackety-yacked
he could have yackety-yacked
we could have yackety-yacked
you could have yackety-yacked
they could have yackety-yacked	I could have been yackety-yacking
you could have been yackety-yacking
he could have been yackety-yacking
we could have been yackety-yacking
you could have been yackety-yacking
they could have been yackety-yacking	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I couldn't yackety-yack
you couldn't yackety-yack
he couldn't yackety-yack
we couldn't yackety-yack
you couldn't yackety-yack
they couldn't yackety-yack 	I couldn't be yackety-yacking
you couldn't be yackety-yacking
he couldn't be yackety-yacking
we couldn't be yackety-yacking
you couldn't be yackety-yacking
they couldn't be yackety-yacking	I couldn't have yackety-yacked
you couldn't have yackety-yacked
he couldn't have yackety-yacked
we couldn't have yackety-yacked
you couldn't have yackety-yacked
they couldn't have yackety-yacked	I couldn't have been yackety-yacking
you couldn't have been yackety-yacking
he couldn't have been yackety-yacking
we couldn't have been yackety-yacking
you couldn't have been yackety-yacking
they couldn't have been yackety-yacking	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I yackety-yack?
could you yackety-yack?
could he yackety-yack?
could we yackety-yack?
could you yackety-yack?
could they yackety-yack? 	could I be yackety-yacking?
could you be yackety-yacking?
could he be yackety-yacking?
could we be yackety-yacking?
could you be yackety-yacking?
could they be yackety-yacking? 	could I have yackety-yacked?
could you have yackety-yacked?
could he have yackety-yacked?
could we have yackety-yacked?
could you have yackety-yacked?
could they have yackety-yacked? 	could I have been yackety-yacking?
could you have been yackety-yacking?
could he have been yackety-yacking?
could we have been yackety-yacking?
could you have been yackety-yacking?
could they have been yackety-yacking? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
couldn't I yackety-yack?
couldn't you yackety-yack?
couldn't he yackety-yack?
couldn't we yackety-yack?
couldn't you yackety-yack?
couldn't they yackety-yack? 	couldn't I be yackety-yacking?
couldn't you be yackety-yacking?
couldn't he be yackety-yacking?
couldn't we be yackety-yacking?
couldn't you be yackety-yacking?
couldn't they be yackety-yacking? 	couldn't I have yackety-yacked?
couldn't you have yackety-yacked?
couldn't he have yackety-yacked?
couldn't we have yackety-yacked?
couldn't you have yackety-yacked?
couldn't they have yackety-yacked? 	couldn't I have been yackety-yacking?
couldn't you have been yackety-yacking?
couldn't he have been yackety-yacking?
couldn't we have been yackety-yacking?
couldn't you have been yackety-yacking?
couldn't they have been yackety-yacking?