Trimming video clips in Timeline view
To trim a video clip by dragging in the Timeline:
1 In the Timeline view, select the video clip you want to change, then hover the cursor over the start or end edge of the video clip until the cursor becomes a double-edged arrow.
2 To adjust the video clip, do one of the following:
n To trim the video clip at the start point, drag the front edge of the video clip to the right.
n To trim the video clip at its end point, drag the back edge of the video clip to the left.