I could dim you could dim he could dim we could dim you could dim they could dim
V-ing form
I could be dimming you could be dimming he could be dimming we could be dimming you could be dimming they could be dimming
Perfect
I could have dimmed you could have dimmed he could have dimmed we could have dimmed you could have dimmed they could have dimmed
V-ing perfect
I could have been dimming you could have been dimming he could have been dimming we could have been dimming you could have been dimming they could have been dimming
Negation
Simple form
I could not dim you could not dim he could not dim we could not dim you could not dim they could not dim
V-ing form
I could not be dimming you could not be dimming he could not be dimming we could not be dimming you could not be dimming they could not be dimming
Perfect
I could not have dimmed you could not have dimmed he could not have dimmed we could not have dimmed you could not have dimmed they could not have dimmed
V-ing perfect
I could not have been dimming you could not have been dimming he could not have been dimming we could not have been dimming you could not have been dimming they could not have been dimming
Interrogative form
Simple form
could I dim? could you dim? could he dim? could we dim? could you dim? could they dim?
V-ing form
could I be dimming? could you be dimming? could he be dimming? could we be dimming? could you be dimming? could they be dimming?
Perfect
could I have dimmed? could you have dimmed? could he have dimmed? could we have dimmed? could you have dimmed? could they have dimmed?
V-ing perfect
could I have been dimming? could you have been dimming? could he have been dimming? could we have been dimming? could you have been dimming? could they have been dimming?
Interro-negative form
Simple form
could I not dim? could you not dim? could he not dim? could we not dim? could you not dim? could they not dim?
V-ing form
could I not be dimming? could you not be dimming? could he not be dimming? could we not be dimming? could you not be dimming? could they not be dimming?
Perfect
could I not have dimmed? could you not have dimmed? could he not have dimmed? could we not have dimmed? could you not have dimmed? could they not have dimmed?
V-ing perfect
could I not have been dimming? could you not have been dimming? could he not have been dimming? could we not have been dimming? could you not have been dimming? could they not have been dimming?