English verb conjugation
COULD LEAVEN

Regular verb: leaven - leavened - leavened

Affirmation

Simple form	V-ing form
I could leaven you could leaven he could leaven we could leaven you could leaven they could leaven	I could be leavening you could be leavening he could be leavening we could be leavening you could be leavening they could be leavening
Perfect	V-ing perfect
I could have leavened you could have leavened he could have leavened we could have leavened you could have leavened they could have leavened	I could have been leavening you could have been leavening he could have been leavening we could have been leavening you could have been leavening they could have been leavening

Negation

Simple form	V-ing form
I could not leaven you could not leaven he could not leaven we could not leaven you could not leaven they could not leaven	I could not be leavening you could not be leavening he could not be leavening we could not be leavening you could not be leavening they could not be leavening
Perfect	V-ing perfect
I could not have leavened you could not have leavened he could not have leavened we could not have leavened you could not have leavened they could not have leavened	I could not have been leavening you could not have been leavening he could not have been leavening we could not have been leavening you could not have been leavening they could not have been leavening

Interrogative form

Simple form	V-ing form
could I leaven? could you leaven? could he leaven? could we leaven? could you leaven? could they leaven?	could I be leavening? could you be leavening? could he be leavening? could we be leavening? could you be leavening? could they be leavening?
Perfect	V-ing perfect
could I have leavened? could you have leavened? could he have leavened? could we have leavened? could you have leavened? could they have leavened?	could I have been leavening? could you have been leavening? could he have been leavening? could we have been leavening? could you have been leavening? could they have been leavening?

Interro-negative form

Simple form	V-ing form
could I not leaven? could you not leaven? could he not leaven? could we not leaven? could you not leaven? could they not leaven?	could I not be leavening? could you not be leavening? could he not be leavening? could we not be leavening? could you not be leavening? could they not be leavening?
Perfect	V-ing perfect
could I not have leavened? could you not have leavened? could he not have leavened? could we not have leavened? could you not have leavened? could they not have leavened?	could I not have been leavening? could you not have been leavening? could he not have been leavening? could we not have been leavening? could you not have been leavening? could they not have been leavening?