English verb conjugation
COULD SMARTEN

Regular verb: smarten - smartened - smartened

Affirmation

Simple form	V-ing form
I could smarten you could smarten he could smarten we could smarten you could smarten they could smarten	I could be smartening you could be smartening he could be smartening we could be smartening you could be smartening they could be smartening
Perfect	V-ing perfect
I could have smartened you could have smartened he could have smartened we could have smartened you could have smartened they could have smartened	I could have been smartening you could have been smartening he could have been smartening we could have been smartening you could have been smartening they could have been smartening

Negation

Simple form	V-ing form
I could not smarten you could not smarten he could not smarten we could not smarten you could not smarten they could not smarten	I could not be smartening you could not be smartening he could not be smartening we could not be smartening you could not be smartening they could not be smartening
Perfect	V-ing perfect
I could not have smartened you could not have smartened he could not have smartened we could not have smartened you could not have smartened they could not have smartened	I could not have been smartening you could not have been smartening he could not have been smartening we could not have been smartening you could not have been smartening they could not have been smartening

Interrogative form

Simple form	V-ing form
could I smarten? could you smarten? could he smarten? could we smarten? could you smarten? could they smarten?	could I be smartening? could you be smartening? could he be smartening? could we be smartening? could you be smartening? could they be smartening?
Perfect	V-ing perfect
could I have smartened? could you have smartened? could he have smartened? could we have smartened? could you have smartened? could they have smartened?	could I have been smartening? could you have been smartening? could he have been smartening? could we have been smartening? could you have been smartening? could they have been smartening?

Interro-negative form

Simple form	V-ing form
could I not smarten? could you not smarten? could he not smarten? could we not smarten? could you not smarten? could they not smarten?	could I not be smartening? could you not be smartening? could he not be smartening? could we not be smartening? could you not be smartening? could they not be smartening?
Perfect	V-ing perfect
could I not have smartened? could you not have smartened? could he not have smartened? could we not have smartened? could you not have smartened? could they not have smartened?	could I not have been smartening? could you not have been smartening? could he not have been smartening? could we not have been smartening? could you not have been smartening? could they not have been smartening?