could creak
Verbo regular: creak - creaked- creaked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could creak
you could creak
he could creak
we could creak
you could creak
they could creak 	I could be creaking
you could be creaking
he could be creaking
we could be creaking
you could be creaking
they could be creaking	I could have creaked
you could have creaked
he could have creaked
we could have creaked
you could have creaked
they could have creaked	I could have been creaking
you could have been creaking
he could have been creaking
we could have been creaking
you could have been creaking
they could have been creaking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I couldn't creak
you couldn't creak
he couldn't creak
we couldn't creak
you couldn't creak
they couldn't creak 	I couldn't be creaking
you couldn't be creaking
he couldn't be creaking
we couldn't be creaking
you couldn't be creaking
they couldn't be creaking	I couldn't have creaked
you couldn't have creaked
he couldn't have creaked
we couldn't have creaked
you couldn't have creaked
they couldn't have creaked	I couldn't have been creaking
you couldn't have been creaking
he couldn't have been creaking
we couldn't have been creaking
you couldn't have been creaking
they couldn't have been creaking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I creak?
could you creak?
could he creak?
could we creak?
could you creak?
could they creak? 	could I be creaking?
could you be creaking?
could he be creaking?
could we be creaking?
could you be creaking?
could they be creaking? 	could I have creaked?
could you have creaked?
could he have creaked?
could we have creaked?
could you have creaked?
could they have creaked? 	could I have been creaking?
could you have been creaking?
could he have been creaking?
could we have been creaking?
could you have been creaking?
could they have been creaking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
couldn't I creak?
couldn't you creak?
couldn't he creak?
couldn't we creak?
couldn't you creak?
couldn't they creak? 	couldn't I be creaking?
couldn't you be creaking?
couldn't he be creaking?
couldn't we be creaking?
couldn't you be creaking?
couldn't they be creaking? 	couldn't I have creaked?
couldn't you have creaked?
couldn't he have creaked?
couldn't we have creaked?
couldn't you have creaked?
couldn't they have creaked? 	couldn't I have been creaking?
couldn't you have been creaking?
couldn't he have been creaking?
couldn't we have been creaking?
couldn't you have been creaking?
couldn't they have been creaking?