This is common expression we use in English when two people get married.
It's an informal expression.
The expression to Tie the knot = to get married.
You will quite often hear people talking about their friends who have recently tied the knot.
Maybe it was family member that recently married.
- Bill and Sara tied the knot last Saturday.
- I know I am getting old but I am not ready to tie the knot just yet.
Remember to start using the expression as soon as you can. Use it with friends but remember that it is informal. So don't use it in formal situations.
Here's another English expression for you to learn.
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