I have trouble knowing when and where to use these words. Take these examples:<br/><br/>1. "I take a 60-second break <b>between</b> sets when weight-lifting."<br/><br/>2. "I take a 60-second break <b>inbetween</b> sets when weight-lifting."<br/><br/>Which is correct and why? Thanks! (I checked dictionary.com but I need a clearer answer.)