English verb conjugation
COULD SMOOTH

Regular verb: smooth - smoothed - smoothed

Affirmation

Simple form	V-ing form
I could smooth you could smooth he could smooth we could smooth you could smooth they could smooth	I could be smoothing you could be smoothing he could be smoothing we could be smoothing you could be smoothing they could be smoothing
Perfect	V-ing perfect
I could have smoothed you could have smoothed he could have smoothed we could have smoothed you could have smoothed they could have smoothed	I could have been smoothing you could have been smoothing he could have been smoothing we could have been smoothing you could have been smoothing they could have been smoothing

Negation

Simple form	V-ing form
I couldn't smooth you couldn't smooth he couldn't smooth we couldn't smooth you couldn't smooth they couldn't smooth	I couldn't be smoothing you couldn't be smoothing he couldn't be smoothing we couldn't be smoothing you couldn't be smoothing they couldn't be smoothing
Perfect	V-ing perfect
I couldn't have smoothed you couldn't have smoothed he couldn't have smoothed we couldn't have smoothed you couldn't have smoothed they couldn't have smoothed	I couldn't have been smoothing you couldn't have been smoothing he couldn't have been smoothing we couldn't have been smoothing you couldn't have been smoothing they couldn't have been smoothing

Interrogative form

Simple form	V-ing form
could I smooth? could you smooth? could he smooth? could we smooth? could you smooth? could they smooth?	could I be smoothing? could you be smoothing? could he be smoothing? could we be smoothing? could you be smoothing? could they be smoothing?
Perfect	V-ing perfect
could I have smoothed? could you have smoothed? could he have smoothed? could we have smoothed? could you have smoothed? could they have smoothed?	could I have been smoothing? could you have been smoothing? could he have been smoothing? could we have been smoothing? could you have been smoothing? could they have been smoothing?

Interro-negative form

Simple form	V-ing form
couldn't I smooth? couldn't you smooth? couldn't he smooth? couldn't we smooth? couldn't you smooth? couldn't they smooth?	couldn't I be smoothing? couldn't you be smoothing? couldn't he be smoothing? couldn't we be smoothing? couldn't you be smoothing? couldn't they be smoothing?
Perfect	V-ing perfect
couldn't I have smoothed? couldn't you have smoothed? couldn't he have smoothed? couldn't we have smoothed? couldn't you have smoothed? couldn't they have smoothed?	couldn't I have been smoothing? couldn't you have been smoothing? couldn't he have been smoothing? couldn't we have been smoothing? couldn't you have been smoothing? couldn't they have been smoothing?