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 he 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 he 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 he 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 he 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 could not stain sth you could not stain sth he could not stain sth we could not stain sth you could not stain sth they could not stain sth	I could not be stain sthing you could not be stain sthing he could not be stain sthing we could not be stain sthing you could not be stain sthing they could not be stain sthing
Perfect	V-ing perfect
I could not have stain sthed you could not have stain sthed he could not have stain sthed we could not have stain sthed you could not have stain sthed they could not have stain sthed	I could not have been stain sthing you could not have been stain sthing he could not have been stain sthing we could not have been stain sthing you could not have been stain sthing they could not have been stain sthing

Interrogative form

Simple form	V-ing form
could I stain sth? could you stain sth? could he 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 he 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 he 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 he 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
could I not stain sth? could you not stain sth? could he not stain sth? could we not stain sth? could you not stain sth? could they not stain sth?	could I not be stain sthing? could you not be stain sthing? could he not be stain sthing? could we not be stain sthing? could you not be stain sthing? could they not be stain sthing?
Perfect	V-ing perfect
could I not have stain sthed? could you not have stain sthed? could he not have stain sthed? could we not have stain sthed? could you not have stain sthed? could they not have stain sthed?	could I not have been stain sthing? could you not have been stain sthing? could he not have been stain sthing? could we not have been stain sthing? could you not have been stain sthing? could they not have been stain sthing?