English verb conjugation
COULD SMARTEN

Regular verb: smarten - smartened - smartened

Affirmation

Simple form	V-ing form
I could smarten you could smarten she could smarten we could smarten you could smarten they could smarten	I could be smartening you could be smartening she 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 she 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 she 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 couldn't smarten you couldn't smarten she couldn't smarten we couldn't smarten you couldn't smarten they couldn't smarten	I couldn't be smartening you couldn't be smartening she couldn't be smartening we couldn't be smartening you couldn't be smartening they couldn't be smartening
Perfect	V-ing perfect
I couldn't have smartened you couldn't have smartened she couldn't have smartened we couldn't have smartened you couldn't have smartened they couldn't have smartened	I couldn't have been smartening you couldn't have been smartening she couldn't have been smartening we couldn't have been smartening you couldn't have been smartening they couldn't have been smartening

Interrogative form

Simple form	V-ing form
could I smarten? could you smarten? could she smarten? could we smarten? could you smarten? could they smarten?	could I be smartening? could you be smartening? could she 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 she 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 she 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
couldn't I smarten? couldn't you smarten? couldn't she smarten? couldn't we smarten? couldn't you smarten? couldn't they smarten?	couldn't I be smartening? couldn't you be smartening? couldn't she be smartening? couldn't we be smartening? couldn't you be smartening? couldn't they be smartening?
Perfect	V-ing perfect
couldn't I have smartened? couldn't you have smartened? couldn't she have smartened? couldn't we have smartened? couldn't you have smartened? couldn't they have smartened?	couldn't I have been smartening? couldn't you have been smartening? couldn't she have been smartening? couldn't we have been smartening? couldn't you have been smartening? couldn't they have been smartening?