Splitting events in Sony Vegas can be very helpful when editing. It allows you to break a single event into multiple sections that you can edit independently. Position the cursor where you want to split the event and hit the shortcut key “S” on your keyboard. This can also be done within the menu bar by going to Edit > Split.
An alternative would be to hold Ctrl + Alt + Shift and click where you want to split the event. You can also hold Ctrl + Alt + Shift and drag over an event to split it at the point you click and trim it.