How do you put videos in slow motion using windows movie maker?

I want to put a youtube video into slow motion, how do I do it?How do you put videos in slow motion using windows movie maker?If you've already downloaded the video file, then you can just paste that onto the timeline. From there, all you need to do is open the Effects library (or right click on the video itself and select "Add Effect") and apply the Slow Down, One Half effect. You won't be able to do anything about the video speed if the file's still on YouTube, though. There are lots of tutorials and suggestions about how to get it from there, so I won't go into all that.