视频对话：
The captain has turned on the fasten seatbelt sign. Please make sure your seatbelts are securely fastened.
机长指示系好安全带。请确保您的安全带已系紧。

本期学习词汇：
fasten
v. 扣牢；系牢；

例句：

1. She got quickly into her Mini and fastened the seat-belt.
她迅速钻进她的 Mini 车里并系紧安全带。
2. Her long fair hair was fastened at the nape of her neck by an elastic band.
她用皮筋将金色长发扎在脑后。
3. The little boy has learnt to fasten shoelaces.
这小男孩已学会系鞋带了。