It is understood that there is no better explanation because of multi-speed viewing, and the effect is not very good, so it was cancelled. Another situation is that students are afraid of brushing classes.

Alternatively, you can try the following methods to speed up video viewing:

1. Open the video webpage.

2.Ctrl+Shift+i opens the development tool.

3. Click the upper right arrow, click the video, click the code selected below, right-click "Copy", and then click "Copy Selector".

4. Click "Console" and copy the code document.querySelector ('here, change it to what we copied in the previous step'). PlaybackRate = 16.0 Go below and press Enter.

See the effect.