English verb conjugation
COULD WATERPROOF

Regular verb: waterproof - waterproofed - waterproofed

Affirmation

Simple form	V-ing form
I could waterproof you could waterproof he could waterproof we could waterproof you could waterproof they could waterproof	I could be waterproofing you could be waterproofing he could be waterproofing we could be waterproofing you could be waterproofing they could be waterproofing
Perfect	V-ing perfect
I could have waterproofed you could have waterproofed he could have waterproofed we could have waterproofed you could have waterproofed they could have waterproofed	I could have been waterproofing you could have been waterproofing he could have been waterproofing we could have been waterproofing you could have been waterproofing they could have been waterproofing

Negation

Simple form	V-ing form
I couldn't waterproof you couldn't waterproof he couldn't waterproof we couldn't waterproof you couldn't waterproof they couldn't waterproof	I couldn't be waterproofing you couldn't be waterproofing he couldn't be waterproofing we couldn't be waterproofing you couldn't be waterproofing they couldn't be waterproofing
Perfect	V-ing perfect
I couldn't have waterproofed you couldn't have waterproofed he couldn't have waterproofed we couldn't have waterproofed you couldn't have waterproofed they couldn't have waterproofed	I couldn't have been waterproofing you couldn't have been waterproofing he couldn't have been waterproofing we couldn't have been waterproofing you couldn't have been waterproofing they couldn't have been waterproofing

Interrogative form

Simple form	V-ing form
could I waterproof? could you waterproof? could he waterproof? could we waterproof? could you waterproof? could they waterproof?	could I be waterproofing? could you be waterproofing? could he be waterproofing? could we be waterproofing? could you be waterproofing? could they be waterproofing?
Perfect	V-ing perfect
could I have waterproofed? could you have waterproofed? could he have waterproofed? could we have waterproofed? could you have waterproofed? could they have waterproofed?	could I have been waterproofing? could you have been waterproofing? could he have been waterproofing? could we have been waterproofing? could you have been waterproofing? could they have been waterproofing?

Interro-negative form

Simple form	V-ing form
couldn't I waterproof? couldn't you waterproof? couldn't he waterproof? couldn't we waterproof? couldn't you waterproof? couldn't they waterproof?	couldn't I be waterproofing? couldn't you be waterproofing? couldn't he be waterproofing? couldn't we be waterproofing? couldn't you be waterproofing? couldn't they be waterproofing?
Perfect	V-ing perfect
couldn't I have waterproofed? couldn't you have waterproofed? couldn't he have waterproofed? couldn't we have waterproofed? couldn't you have waterproofed? couldn't they have waterproofed?	couldn't I have been waterproofing? couldn't you have been waterproofing? couldn't he have been waterproofing? couldn't we have been waterproofing? couldn't you have been waterproofing? couldn't they have been waterproofing?