Transitions add a visual effect to the beginning or end of a clip, shape, or text on the timeline.
Add a transition
Click and drag a transition from the Video Effects view onto the beginning or end of a clip, shape, or text object on the timeline. See About the Video Effects view.
Change the transition duration
Click to select the transition on the timeline.
Drag the end of the transition in or out. Note: Try dragging the Timeline Zoom Scale slider below the timeline to the right to zoom in for precise editing.
Delete a transition
Click to select the transition on the timeline.
Select Edit > Delete or press the Delete key.