I could soundproof you could soundproof he could soundproof we could soundproof you could soundproof they could soundproof
V-ing form
I could be soundproofing you could be soundproofing he could be soundproofing we could be soundproofing you could be soundproofing they could be soundproofing
Perfect
I could have soundproofed you could have soundproofed he could have soundproofed we could have soundproofed you could have soundproofed they could have soundproofed
V-ing perfect
I could have been soundproofing you could have been soundproofing he could have been soundproofing we could have been soundproofing you could have been soundproofing they could have been soundproofing
Negation
Simple form
I couldn't soundproof you couldn't soundproof he couldn't soundproof we couldn't soundproof you couldn't soundproof they couldn't soundproof
V-ing form
I couldn't be soundproofing you couldn't be soundproofing he couldn't be soundproofing we couldn't be soundproofing you couldn't be soundproofing they couldn't be soundproofing
Perfect
I couldn't have soundproofed you couldn't have soundproofed he couldn't have soundproofed we couldn't have soundproofed you couldn't have soundproofed they couldn't have soundproofed
V-ing perfect
I couldn't have been soundproofing you couldn't have been soundproofing he couldn't have been soundproofing we couldn't have been soundproofing you couldn't have been soundproofing they couldn't have been soundproofing
Interrogative form
Simple form
could I soundproof? could you soundproof? could he soundproof? could we soundproof? could you soundproof? could they soundproof?
V-ing form
could I be soundproofing? could you be soundproofing? could he be soundproofing? could we be soundproofing? could you be soundproofing? could they be soundproofing?
Perfect
could I have soundproofed? could you have soundproofed? could he have soundproofed? could we have soundproofed? could you have soundproofed? could they have soundproofed?
V-ing perfect
could I have been soundproofing? could you have been soundproofing? could he have been soundproofing? could we have been soundproofing? could you have been soundproofing? could they have been soundproofing?
Interro-negative form
Simple form
couldn't I soundproof? couldn't you soundproof? couldn't he soundproof? couldn't we soundproof? couldn't you soundproof? couldn't they soundproof?
V-ing form
couldn't I be soundproofing? couldn't you be soundproofing? couldn't he be soundproofing? couldn't we be soundproofing? couldn't you be soundproofing? couldn't they be soundproofing?
Perfect
couldn't I have soundproofed? couldn't you have soundproofed? couldn't he have soundproofed? couldn't we have soundproofed? couldn't you have soundproofed? couldn't they have soundproofed?
V-ing perfect
couldn't I have been soundproofing? couldn't you have been soundproofing? couldn't he have been soundproofing? couldn't we have been soundproofing? couldn't you have been soundproofing? couldn't they have been soundproofing?