buckle up 系好安全带，把…扣紧

　　Hey man! Buckle up. It's safe. It's the law!

　　哥们，系上安全带！这样才安全啊，而且这是法律规定。

　　Please buckle up now. We're about to land.

　　现在请系好安全带，我们要着陆了。

　　疯狂练习吧！