could smarten
Regular verb: smarten - smartened- smartened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
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? 	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 	Perfect 	V-ing perfect 	
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? 	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?