Improve the given sentence if necessary. Decide one way or the other; you can?t be sitting on the fence forever.

?Sitting on the fence? is the correct idiom used. It is used to describe a person?s lack of decisiveness, neutrality or hesitance to choose between two sides in an argument or a competition, or inability to decide due to lack of courage. Thus, the sentence is grammatically and contextually correct. Thus, the correct formation would be, ?Decide one way or the other; you can?t be sitting on the fence forever?.