Inserts / Cutaways can be short filler shots such as walking, waving, running, laughing, etc. Their purpose is to break up the long shots for a professional looking product.
Add an Insert Shot: Double click on any filler shot to open it, then use 'Mark In' to set a start point and 'Mark Out' to set an end point under your Source Monitor to select the parameters of your filler shot:
Your layers will look like:
This is a little extra editing with a big payoff: your video will appear to move faster and will have a higher production value - which translates as additional grade points for your group.