English verb conjugation
COULD STAY

Regular verb: stay - stayed - stayed

Affirmation

Simple form	V-ing form
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
Perfect	V-ing perfect
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
I couldn't stay you couldn't stay he couldn't stay we couldn't stay you couldn't stay they couldn't stay	I couldn't be staying you couldn't be staying he couldn't be staying we couldn't be staying you couldn't be staying they couldn't be staying
Perfect	V-ing perfect
I couldn't have stayed you couldn't have stayed he couldn't have stayed we couldn't have stayed you couldn't have stayed they couldn't have stayed	I couldn't have been staying you couldn't have been staying he couldn't have been staying we couldn't have been staying you couldn't have been staying they couldn't have been staying

Interrogative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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
couldn't I stay? couldn't you stay? couldn't he stay? couldn't we stay? couldn't you stay? couldn't they stay?	couldn't I be staying? couldn't you be staying? couldn't he be staying? couldn't we be staying? couldn't you be staying? couldn't they be staying?
Perfect	V-ing perfect
couldn't I have stayed? couldn't you have stayed? couldn't he have stayed? couldn't we have stayed? couldn't you have stayed? couldn't they have stayed?	couldn't I have been staying? couldn't you have been staying? couldn't he have been staying? couldn't we have been staying? couldn't you have been staying? couldn't they have been staying?