English verb conjugation
COULD PILE

Regular verb: pile - piled - piled

Affirmation

Simple form	V-ing form
I could pile you could pile he could pile we could pile you could pile they could pile	I could be piling you could be piling he could be piling we could be piling you could be piling they could be piling
Perfect	V-ing perfect
I could have piled you could have piled he could have piled we could have piled you could have piled they could have piled	I could have been piling you could have been piling he could have been piling we could have been piling you could have been piling they could have been piling

Negation

Simple form	V-ing form
I couldn't pile you couldn't pile he couldn't pile we couldn't pile you couldn't pile they couldn't pile	I couldn't be piling you couldn't be piling he couldn't be piling we couldn't be piling you couldn't be piling they couldn't be piling
Perfect	V-ing perfect
I couldn't have piled you couldn't have piled he couldn't have piled we couldn't have piled you couldn't have piled they couldn't have piled	I couldn't have been piling you couldn't have been piling he couldn't have been piling we couldn't have been piling you couldn't have been piling they couldn't have been piling

Interrogative form

Simple form	V-ing form
could I pile? could you pile? could he pile? could we pile? could you pile? could they pile?	could I be piling? could you be piling? could he be piling? could we be piling? could you be piling? could they be piling?
Perfect	V-ing perfect
could I have piled? could you have piled? could he have piled? could we have piled? could you have piled? could they have piled?	could I have been piling? could you have been piling? could he have been piling? could we have been piling? could you have been piling? could they have been piling?

Interro-negative form

Simple form	V-ing form
couldn't I pile? couldn't you pile? couldn't he pile? couldn't we pile? couldn't you pile? couldn't they pile?	couldn't I be piling? couldn't you be piling? couldn't he be piling? couldn't we be piling? couldn't you be piling? couldn't they be piling?
Perfect	V-ing perfect
couldn't I have piled? couldn't you have piled? couldn't he have piled? couldn't we have piled? couldn't you have piled? couldn't they have piled?	couldn't I have been piling? couldn't you have been piling? couldn't he have been piling? couldn't we have been piling? couldn't you have been piling? couldn't they have been piling?