Trimming your video clips is one of the most basic ways that we look to for clip editing when putting together sequences. Trimming means that you are shortening the clips by either taking off a little at the beginning or end while not affecting the source clip whatsoever. You must be able to do this in all video editing software you use, and Windows Movie Maker is no different.
Take a clip and put it into the Timeline. It is better to use the Timeline view in your Windows Movie Maker project for this purpose. When it is in there, play through the clip to find the places you would want to cut out. Go and put the cursor either on the beginning or end of the clip depending on what you want to cut out.
You will notice that the cursor becomes a red doublesided arrow, and there will be a message that reads “Click and drag to trim the clip.” Now just click down, and start moving toward the center of the clip. This will begin shortening the clip from the beginning or end of the clip, cutting off all that you moved in from. This will not affect the clip as it sits in the Collections, just what is in the Timeline. If you do not like what you just did, you can press down again and stretch it back to its original position.
Working in a Video Sequence
If you shorten the clip inward from the beginning it will realign itself with its beginning being at the beginning of the Timeline or the end of the previous clip, depending on its original position. This is done so that there are no gaps between clips that appear. All clips around it will realign themselves to take care of the gapping issue as well.
Since Windows Movie Maker usually breaks up larger clips into smaller ones you may want to be careful while Trimming clips because they are short in length and you have to remain accurate. Try doing a test run of the trim before you leave the edit on the Timeline sequence clip.