You might want to apply different effects to different parts of a clip. For example, to speed up the first part but leave the second part at normal speed. To do this, you cut a clip into separate pieces, and then apply effects and transitions to those pieces. You can split a clip in a movie by using the Split Clip button on the current-time indicator. It cuts one or more selected clips at the current‑time indicator.
Splitting a clip divides it into two parts, creating a new and separate instance of the original clip. If the clip is linked to another clip, a new instance of the linked clip is created as well.
The two resulting clips, when combined, represent the original clip. The resulting clips are full versions of the original clip, but with the In or Out points changed to match the location marked by the tool. You can select and delete these clips.
If you want to change effect settings over time, you don’t have to split the clip. You can apply keyframes to a single clip instead.
You can split a clip at any frame, creating one clip that ends, and another that begins, at that frame. You can edit the two resulting clips as you would any other clips.
You can simultaneously split two or more layered clips (clips that overlap in the Expert view timeline).