I could window-shop you could window-shop he could window-shop we could window-shop you could window-shop they could window-shop
V-ing form
I could be window-shoping you could be window-shoping he could be window-shoping we could be window-shoping you could be window-shoping they could be window-shoping
Perfect
I could have window-shoped you could have window-shoped he could have window-shoped we could have window-shoped you could have window-shoped they could have window-shoped
V-ing perfect
I could have been window-shoping you could have been window-shoping he could have been window-shoping we could have been window-shoping you could have been window-shoping they could have been window-shoping
Negation
Simple form
I could not window-shop you could not window-shop he could not window-shop we could not window-shop you could not window-shop they could not window-shop
V-ing form
I could not be window-shoping you could not be window-shoping he could not be window-shoping we could not be window-shoping you could not be window-shoping they could not be window-shoping
Perfect
I could not have window-shoped you could not have window-shoped he could not have window-shoped we could not have window-shoped you could not have window-shoped they could not have window-shoped
V-ing perfect
I could not have been window-shoping you could not have been window-shoping he could not have been window-shoping we could not have been window-shoping you could not have been window-shoping they could not have been window-shoping
Interrogative form
Simple form
could I window-shop? could you window-shop? could he window-shop? could we window-shop? could you window-shop? could they window-shop?
V-ing form
could I be window-shoping? could you be window-shoping? could he be window-shoping? could we be window-shoping? could you be window-shoping? could they be window-shoping?
Perfect
could I have window-shoped? could you have window-shoped? could he have window-shoped? could we have window-shoped? could you have window-shoped? could they have window-shoped?
V-ing perfect
could I have been window-shoping? could you have been window-shoping? could he have been window-shoping? could we have been window-shoping? could you have been window-shoping? could they have been window-shoping?
Interro-negative form
Simple form
could I not window-shop? could you not window-shop? could he not window-shop? could we not window-shop? could you not window-shop? could they not window-shop?
V-ing form
could I not be window-shoping? could you not be window-shoping? could he not be window-shoping? could we not be window-shoping? could you not be window-shoping? could they not be window-shoping?
Perfect
could I not have window-shoped? could you not have window-shoped? could he not have window-shoped? could we not have window-shoped? could you not have window-shoped? could they not have window-shoped?
V-ing perfect
could I not have been window-shoping? could you not have been window-shoping? could he not have been window-shoping? could we not have been window-shoping? could you not have been window-shoping? could they not have been window-shoping?