English verb conjugation
COULD PROOF

Regular verb: proof - proofed - proofed

Affirmation

Simple form	V-ing form
I could proof you could proof he could proof we could proof you could proof they could proof	I could be proofing you could be proofing he could be proofing we could be proofing you could be proofing they could be proofing
Perfect	V-ing perfect
I could have proofed you could have proofed he could have proofed we could have proofed you could have proofed they could have proofed	I could have been proofing you could have been proofing he could have been proofing we could have been proofing you could have been proofing they could have been proofing

Negation

Simple form	V-ing form
I could not proof you could not proof he could not proof we could not proof you could not proof they could not proof	I could not be proofing you could not be proofing he could not be proofing we could not be proofing you could not be proofing they could not be proofing
Perfect	V-ing perfect
I could not have proofed you could not have proofed he could not have proofed we could not have proofed you could not have proofed they could not have proofed	I could not have been proofing you could not have been proofing he could not have been proofing we could not have been proofing you could not have been proofing they could not have been proofing

Interrogative form

Simple form	V-ing form
could I proof? could you proof? could he proof? could we proof? could you proof? could they proof?	could I be proofing? could you be proofing? could he be proofing? could we be proofing? could you be proofing? could they be proofing?
Perfect	V-ing perfect
could I have proofed? could you have proofed? could he have proofed? could we have proofed? could you have proofed? could they have proofed?	could I have been proofing? could you have been proofing? could he have been proofing? could we have been proofing? could you have been proofing? could they have been proofing?

Interro-negative form

Simple form	V-ing form
could I not proof? could you not proof? could he not proof? could we not proof? could you not proof? could they not proof?	could I not be proofing? could you not be proofing? could he not be proofing? could we not be proofing? could you not be proofing? could they not be proofing?
Perfect	V-ing perfect
could I not have proofed? could you not have proofed? could he not have proofed? could we not have proofed? could you not have proofed? could they not have proofed?	could I not have been proofing? could you not have been proofing? could he not have been proofing? could we not have been proofing? could you not have been proofing? could they not have been proofing?