English verb conjugation
COULD MIX

Regular verb: mix - mixed - mixed

Affirmation

Simple form	V-ing form
I could mix you could mix he could mix we could mix you could mix they could mix	I could be mixing you could be mixing he could be mixing we could be mixing you could be mixing they could be mixing
Perfect	V-ing perfect
I could have mixed you could have mixed he could have mixed we could have mixed you could have mixed they could have mixed	I could have been mixing you could have been mixing he could have been mixing we could have been mixing you could have been mixing they could have been mixing

Negation

Simple form	V-ing form
I couldn't mix you couldn't mix he couldn't mix we couldn't mix you couldn't mix they couldn't mix	I couldn't be mixing you couldn't be mixing he couldn't be mixing we couldn't be mixing you couldn't be mixing they couldn't be mixing
Perfect	V-ing perfect
I couldn't have mixed you couldn't have mixed he couldn't have mixed we couldn't have mixed you couldn't have mixed they couldn't have mixed	I couldn't have been mixing you couldn't have been mixing he couldn't have been mixing we couldn't have been mixing you couldn't have been mixing they couldn't have been mixing

Interrogative form

Simple form	V-ing form
could I mix? could you mix? could he mix? could we mix? could you mix? could they mix?	could I be mixing? could you be mixing? could he be mixing? could we be mixing? could you be mixing? could they be mixing?
Perfect	V-ing perfect
could I have mixed? could you have mixed? could he have mixed? could we have mixed? could you have mixed? could they have mixed?	could I have been mixing? could you have been mixing? could he have been mixing? could we have been mixing? could you have been mixing? could they have been mixing?

Interro-negative form

Simple form	V-ing form
couldn't I mix? couldn't you mix? couldn't he mix? couldn't we mix? couldn't you mix? couldn't they mix?	couldn't I be mixing? couldn't you be mixing? couldn't he be mixing? couldn't we be mixing? couldn't you be mixing? couldn't they be mixing?
Perfect	V-ing perfect
couldn't I have mixed? couldn't you have mixed? couldn't he have mixed? couldn't we have mixed? couldn't you have mixed? couldn't they have mixed?	couldn't I have been mixing? couldn't you have been mixing? couldn't he have been mixing? couldn't we have been mixing? couldn't you have been mixing? couldn't they have been mixing?