I've watched this video every so often since I was a teenager, and it was only when I bought it on DVD and turned on the subtitles that I could make out most of it. And I'm a native English speaker. Of course it doesn't help that the lyrics don't mean much even when you know what they say. This is probably the only English song whose lyrics I had real trouble understanding. I happened to watch it again this evening so I thought of posting this.

LOL, it kind of reminds me of this comic:
https://xkcd.com/1538/
A lot of pop songs I can generally understand the lyrics to, but a lot of times there are one or two surprises when I go and read them.