You can display subtitles in many different languages, as auto-translated by YouTube.
Once you click to start the video, the YouTube playbar is shown (you can click pause now if you like).
- First, you will need to turn on the subtitles.
- Click the Gear icon then click Subtitles/CC. (see below)
- Choose your language in the list.
If your language is not there, you should first select "English", then click Subtitles/CC again, then there should be an option "Auto-translate" at the bottom. Click on that and choose from over 100 languages.
The subtitles will be auto-translated from the English source.