could waterproof
Regular verb: waterproof - waterproofed- waterproofed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could waterproof
you could waterproof
she could waterproof
we could waterproof
you could waterproof
they could waterproof 	I could be waterproofing
you could be waterproofing
she could be waterproofing
we could be waterproofing
you could be waterproofing
they could be waterproofing	I could have waterproofed
you could have waterproofed
she 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
she 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 	Perfect 	V-ing perfect 	
I could not waterproof
you could not waterproof
she could not waterproof
we could not waterproof
you could not waterproof
they could not waterproof 	I could not be waterproofing
you could not be waterproofing
she could not be waterproofing
we could not be waterproofing
you could not be waterproofing
they could not be waterproofing	I could not have waterproofed
you could not have waterproofed
she could not have waterproofed
we could not have waterproofed
you could not have waterproofed
they could not have waterproofed	I could not have been waterproofing
you could not have been waterproofing
she could not have been waterproofing
we could not have been waterproofing
you could not have been waterproofing
they could not have been waterproofing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I waterproof?
could you waterproof?
could she waterproof?
could we waterproof?
could you waterproof?
could they waterproof? 	could I be waterproofing?
could you be waterproofing?
could she be waterproofing?
could we be waterproofing?
could you be waterproofing?
could they be waterproofing? 	could I have waterproofed?
could you have waterproofed?
could she 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 she 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 	Perfect 	V-ing perfect 	
could I not waterproof?
could you not waterproof?
could she not waterproof?
could we not waterproof?
could you not waterproof?
could they not waterproof? 	could I not be waterproofing?
could you not be waterproofing?
could she not be waterproofing?
could we not be waterproofing?
could you not be waterproofing?
could they not be waterproofing? 	could I not have waterproofed?
could you not have waterproofed?
could she not have waterproofed?
could we not have waterproofed?
could you not have waterproofed?
could they not have waterproofed? 	could I not have been waterproofing?
could you not have been waterproofing?
could she not have been waterproofing?
could we not have been waterproofing?
could you not have been waterproofing?
could they not have been waterproofing?