Antonyms for the phrase "began where left off" could include words like ended, concluded, finished, stopped, and ceased. These words signify a break or interruption in an activity, which is different from the phrase "began where left off," which implies continuing from a previous point. The opposite of starting from where you left off could mean starting from scratch, starting anew, starting afresh, or beginning again. These antonyms indicate a sense of starting over, whether due to a change in circumstance or a desire for a fresh start. In any case, understanding antonyms helps to broaden one's vocabulary and provides clarity in communication.