could stay
Regular verb: stay - stayed- stayed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could stay
you could stay
he could stay
we could stay
you could stay
they could stay 	I could be staying
you could be staying
he could be staying
we could be staying
you could be staying
they could be staying	I could have stayed
you could have stayed
he could have stayed
we could have stayed
you could have stayed
they could have stayed	I could have been staying
you could have been staying
he could have been staying
we could have been staying
you could have been staying
they could have been staying	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not stay
you could not stay
he could not stay
we could not stay
you could not stay
they could not stay 	I could not be staying
you could not be staying
he could not be staying
we could not be staying
you could not be staying
they could not be staying	I could not have stayed
you could not have stayed
he could not have stayed
we could not have stayed
you could not have stayed
they could not have stayed	I could not have been staying
you could not have been staying
he could not have been staying
we could not have been staying
you could not have been staying
they could not have been staying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I stay?
could you stay?
could he stay?
could we stay?
could you stay?
could they stay? 	could I be staying?
could you be staying?
could he be staying?
could we be staying?
could you be staying?
could they be staying? 	could I have stayed?
could you have stayed?
could he have stayed?
could we have stayed?
could you have stayed?
could they have stayed? 	could I have been staying?
could you have been staying?
could he have been staying?
could we have been staying?
could you have been staying?
could they have been staying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not stay?
could you not stay?
could he not stay?
could we not stay?
could you not stay?
could they not stay? 	could I not be staying?
could you not be staying?
could he not be staying?
could we not be staying?
could you not be staying?
could they not be staying? 	could I not have stayed?
could you not have stayed?
could he not have stayed?
could we not have stayed?
could you not have stayed?
could they not have stayed? 	could I not have been staying?
could you not have been staying?
could he not have been staying?
could we not have been staying?
could you not have been staying?
could they not have been staying?