can yack
Verbo regular: yack - yacked- yacked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I can yack
you can yack
he can yack
we can yack
you can yack
they can yack 	I can be yacking
you can be yacking
he can be yacking
we can be yacking
you can be yacking
they can be yacking	I can have yacked
you can have yacked
he can have yacked
we can have yacked
you can have yacked
they can have yacked	I can have been yacking
you can have been yacking
he can have been yacking
we can have been yacking
you can have been yacking
they can have been yacking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I cannot yack
you cannot yack
he cannot yack
we cannot yack
you cannot yack
they cannot yack 	I cannot be yacking
you cannot be yacking
he cannot be yacking
we cannot be yacking
you cannot be yacking
they cannot be yacking	I cannot have yacked
you cannot have yacked
he cannot have yacked
we cannot have yacked
you cannot have yacked
they cannot have yacked	I cannot have been yacking
you cannot have been yacking
he cannot have been yacking
we cannot have been yacking
you cannot have been yacking
they cannot have been yacking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I yack?
can you yack?
can he yack?
can we yack?
can you yack?
can they yack? 	can I be yacking?
can you be yacking?
can he be yacking?
can we be yacking?
can you be yacking?
can they be yacking? 	can I have yacked?
can you have yacked?
can he have yacked?
can we have yacked?
can you have yacked?
can they have yacked? 	can I have been yacking?
can you have been yacking?
can he have been yacking?
can we have been yacking?
can you have been yacking?
can they have been yacking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
can I not yack?
can you not yack?
can he not yack?
can we not yack?
can you not yack?
can they not yack? 	can I not be yacking?
can you not be yacking?
can he not be yacking?
can we not be yacking?
can you not be yacking?
can they not be yacking? 	can I not have yacked?
can you not have yacked?
can he not have yacked?
can we not have yacked?
can you not have yacked?
can they not have yacked? 	can I not have been yacking?
can you not have been yacking?
can he not have been yacking?
can we not have been yacking?
can you not have been yacking?
can they not have been yacking?