English verb conjugation
COULD STAIN STH

Regular verb: stain sth - stain sthed - stain sthed

Warning, this verb may not exist. Conjugation is given as example.

Affirmation

Simple form	V-ing form
I could stain sth you could stain sth she could stain sth we could stain sth you could stain sth they could stain sth	I could be stain sthing you could be stain sthing she could be stain sthing we could be stain sthing you could be stain sthing they could be stain sthing
Perfect	V-ing perfect
I could have stain sthed you could have stain sthed she could have stain sthed we could have stain sthed you could have stain sthed they could have stain sthed	I could have been stain sthing you could have been stain sthing she could have been stain sthing we could have been stain sthing you could have been stain sthing they could have been stain sthing

Negation

Simple form	V-ing form
I couldn't stain sth you couldn't stain sth she couldn't stain sth we couldn't stain sth you couldn't stain sth they couldn't stain sth	I couldn't be stain sthing you couldn't be stain sthing she couldn't be stain sthing we couldn't be stain sthing you couldn't be stain sthing they couldn't be stain sthing
Perfect	V-ing perfect
I couldn't have stain sthed you couldn't have stain sthed she couldn't have stain sthed we couldn't have stain sthed you couldn't have stain sthed they couldn't have stain sthed	I couldn't have been stain sthing you couldn't have been stain sthing she couldn't have been stain sthing we couldn't have been stain sthing you couldn't have been stain sthing they couldn't have been stain sthing

Interrogative form

Simple form	V-ing form
could I stain sth? could you stain sth? could she stain sth? could we stain sth? could you stain sth? could they stain sth?	could I be stain sthing? could you be stain sthing? could she be stain sthing? could we be stain sthing? could you be stain sthing? could they be stain sthing?
Perfect	V-ing perfect
could I have stain sthed? could you have stain sthed? could she have stain sthed? could we have stain sthed? could you have stain sthed? could they have stain sthed?	could I have been stain sthing? could you have been stain sthing? could she have been stain sthing? could we have been stain sthing? could you have been stain sthing? could they have been stain sthing?

Interro-negative form

Simple form	V-ing form
couldn't I stain sth? couldn't you stain sth? couldn't she stain sth? couldn't we stain sth? couldn't you stain sth? couldn't they stain sth?	couldn't I be stain sthing? couldn't you be stain sthing? couldn't she be stain sthing? couldn't we be stain sthing? couldn't you be stain sthing? couldn't they be stain sthing?
Perfect	V-ing perfect
couldn't I have stain sthed? couldn't you have stain sthed? couldn't she have stain sthed? couldn't we have stain sthed? couldn't you have stain sthed? couldn't they have stain sthed?	couldn't I have been stain sthing? couldn't you have been stain sthing? couldn't she have been stain sthing? couldn't we have been stain sthing? couldn't you have been stain sthing? couldn't they have been stain sthing?