Why knot?

Here’s a short explanation from NPR about why shoelaces come untied and what you can do to prevent it. You can read the article, and listen to the story with or without the transcript. To listen click on the “play” button you’ll see in the top-left corner of the article.

The last paragraph in the transcript has one vocabulary we used in Week 1’s class. And the bad joke which I used for the title of this post.

The article mentions this TED Talk about tying your shoes. This talk has been popular with past students, probably because it’s short and easy to understand. It’s also one of the very first TED Talks. Here’s the link to the TED site, where you can watch with a transcript.

Language usage question:

What does the word “nailed” mean in this context? (This is the second paragraph of the transcript.)