English verb conjugation
COULD ROOF

Regular verb: roof - roofed - roofed

Affirmation

Simple form	V-ing form
I could roof you could roof he could roof we could roof you could roof they could roof	I could be roofing you could be roofing he could be roofing we could be roofing you could be roofing they could be roofing
Perfect	V-ing perfect
I could have roofed you could have roofed he could have roofed we could have roofed you could have roofed they could have roofed	I could have been roofing you could have been roofing he could have been roofing we could have been roofing you could have been roofing they could have been roofing

Negation

Simple form	V-ing form
I could not roof you could not roof he could not roof we could not roof you could not roof they could not roof	I could not be roofing you could not be roofing he could not be roofing we could not be roofing you could not be roofing they could not be roofing
Perfect	V-ing perfect
I could not have roofed you could not have roofed he could not have roofed we could not have roofed you could not have roofed they could not have roofed	I could not have been roofing you could not have been roofing he could not have been roofing we could not have been roofing you could not have been roofing they could not have been roofing

Interrogative form

Simple form	V-ing form
could I roof? could you roof? could he roof? could we roof? could you roof? could they roof?	could I be roofing? could you be roofing? could he be roofing? could we be roofing? could you be roofing? could they be roofing?
Perfect	V-ing perfect
could I have roofed? could you have roofed? could he have roofed? could we have roofed? could you have roofed? could they have roofed?	could I have been roofing? could you have been roofing? could he have been roofing? could we have been roofing? could you have been roofing? could they have been roofing?

Interro-negative form

Simple form	V-ing form
could I not roof? could you not roof? could he not roof? could we not roof? could you not roof? could they not roof?	could I not be roofing? could you not be roofing? could he not be roofing? could we not be roofing? could you not be roofing? could they not be roofing?
Perfect	V-ing perfect
could I not have roofed? could you not have roofed? could he not have roofed? could we not have roofed? could you not have roofed? could they not have roofed?	could I not have been roofing? could you not have been roofing? could he not have been roofing? could we not have been roofing? could you not have been roofing? could they not have been roofing?