English verb conjugation
COULD EXCHANGE

Regular verb: exchange - exchanged - exchanged

Affirmation

Simple form	V-ing form
I could exchange you could exchange he could exchange we could exchange you could exchange they could exchange	I could be exchanging you could be exchanging he could be exchanging we could be exchanging you could be exchanging they could be exchanging
Perfect	V-ing perfect
I could have exchanged you could have exchanged he could have exchanged we could have exchanged you could have exchanged they could have exchanged	I could have been exchanging you could have been exchanging he could have been exchanging we could have been exchanging you could have been exchanging they could have been exchanging

Negation

Simple form	V-ing form
I could not exchange you could not exchange he could not exchange we could not exchange you could not exchange they could not exchange	I could not be exchanging you could not be exchanging he could not be exchanging we could not be exchanging you could not be exchanging they could not be exchanging
Perfect	V-ing perfect
I could not have exchanged you could not have exchanged he could not have exchanged we could not have exchanged you could not have exchanged they could not have exchanged	I could not have been exchanging you could not have been exchanging he could not have been exchanging we could not have been exchanging you could not have been exchanging they could not have been exchanging

Interrogative form

Simple form	V-ing form
could I exchange? could you exchange? could he exchange? could we exchange? could you exchange? could they exchange?	could I be exchanging? could you be exchanging? could he be exchanging? could we be exchanging? could you be exchanging? could they be exchanging?
Perfect	V-ing perfect
could I have exchanged? could you have exchanged? could he have exchanged? could we have exchanged? could you have exchanged? could they have exchanged?	could I have been exchanging? could you have been exchanging? could he have been exchanging? could we have been exchanging? could you have been exchanging? could they have been exchanging?

Interro-negative form

Simple form	V-ing form
could I not exchange? could you not exchange? could he not exchange? could we not exchange? could you not exchange? could they not exchange?	could I not be exchanging? could you not be exchanging? could he not be exchanging? could we not be exchanging? could you not be exchanging? could they not be exchanging?
Perfect	V-ing perfect
could I not have exchanged? could you not have exchanged? could he not have exchanged? could we not have exchanged? could you not have exchanged? could they not have exchanged?	could I not have been exchanging? could you not have been exchanging? could he not have been exchanging? could we not have been exchanging? could you not have been exchanging? could they not have been exchanging?