English verb conjugation
COULD HEFT

Regular verb: heft - hefted - hefted

Affirmation

Simple form	V-ing form
I could heft you could heft he could heft we could heft you could heft they could heft	I could be hefting you could be hefting he could be hefting we could be hefting you could be hefting they could be hefting
Perfect	V-ing perfect
I could have hefted you could have hefted he could have hefted we could have hefted you could have hefted they could have hefted	I could have been hefting you could have been hefting he could have been hefting we could have been hefting you could have been hefting they could have been hefting

Negation

Simple form	V-ing form
I could not heft you could not heft he could not heft we could not heft you could not heft they could not heft	I could not be hefting you could not be hefting he could not be hefting we could not be hefting you could not be hefting they could not be hefting
Perfect	V-ing perfect
I could not have hefted you could not have hefted he could not have hefted we could not have hefted you could not have hefted they could not have hefted	I could not have been hefting you could not have been hefting he could not have been hefting we could not have been hefting you could not have been hefting they could not have been hefting

Interrogative form

Simple form	V-ing form
could I heft? could you heft? could he heft? could we heft? could you heft? could they heft?	could I be hefting? could you be hefting? could he be hefting? could we be hefting? could you be hefting? could they be hefting?
Perfect	V-ing perfect
could I have hefted? could you have hefted? could he have hefted? could we have hefted? could you have hefted? could they have hefted?	could I have been hefting? could you have been hefting? could he have been hefting? could we have been hefting? could you have been hefting? could they have been hefting?

Interro-negative form

Simple form	V-ing form
could I not heft? could you not heft? could he not heft? could we not heft? could you not heft? could they not heft?	could I not be hefting? could you not be hefting? could he not be hefting? could we not be hefting? could you not be hefting? could they not be hefting?
Perfect	V-ing perfect
could I not have hefted? could you not have hefted? could he not have hefted? could we not have hefted? could you not have hefted? could they not have hefted?	could I not have been hefting? could you not have been hefting? could he not have been hefting? could we not have been hefting? could you not have been hefting? could they not have been hefting?