Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could clencher you could clencher he could clencher we could clencher you could clencher they could clencher
V-ing form
I could be clenchering you could be clenchering he could be clenchering we could be clenchering you could be clenchering they could be clenchering
Perfect
I could have clenchered you could have clenchered he could have clenchered we could have clenchered you could have clenchered they could have clenchered
V-ing perfect
I could have been clenchering you could have been clenchering he could have been clenchering we could have been clenchering you could have been clenchering they could have been clenchering
Negation
Simple form
I could not clencher you could not clencher he could not clencher we could not clencher you could not clencher they could not clencher
V-ing form
I could not be clenchering you could not be clenchering he could not be clenchering we could not be clenchering you could not be clenchering they could not be clenchering
Perfect
I could not have clenchered you could not have clenchered he could not have clenchered we could not have clenchered you could not have clenchered they could not have clenchered
V-ing perfect
I could not have been clenchering you could not have been clenchering he could not have been clenchering we could not have been clenchering you could not have been clenchering they could not have been clenchering
Interrogative form
Simple form
could I clencher? could you clencher? could he clencher? could we clencher? could you clencher? could they clencher?
V-ing form
could I be clenchering? could you be clenchering? could he be clenchering? could we be clenchering? could you be clenchering? could they be clenchering?
Perfect
could I have clenchered? could you have clenchered? could he have clenchered? could we have clenchered? could you have clenchered? could they have clenchered?
V-ing perfect
could I have been clenchering? could you have been clenchering? could he have been clenchering? could we have been clenchering? could you have been clenchering? could they have been clenchering?
Interro-negative form
Simple form
could I not clencher? could you not clencher? could he not clencher? could we not clencher? could you not clencher? could they not clencher?
V-ing form
could I not be clenchering? could you not be clenchering? could he not be clenchering? could we not be clenchering? could you not be clenchering? could they not be clenchering?
Perfect
could I not have clenchered? could you not have clenchered? could he not have clenchered? could we not have clenchered? could you not have clenchered? could they not have clenchered?
V-ing perfect
could I not have been clenchering? could you not have been clenchering? could he not have been clenchering? could we not have been clenchering? could you not have been clenchering? could they not have been clenchering?