After a bird has flown from one tree to another, what trace does it leave in the air?

当一只鸟从一棵树飞到另外一棵树时，牠在空中留下什么痕迹呢？

Instead of asking for volunteers at the gate to leave overbooked flights, Delta Air Lines now is enabling travelers to bid on the opportunity much earlier in the process.

与其在登机口说服游客自愿离开已经超售的航班，达美航空现在可以让旅行者提前为补偿的现金券竞价，并接受航班变更。

Sometimes I imagine taking a page design that's too crowded and sticking it on a balloon, then blowing air in until everything on the page pulls apart to leave healthy gaps.

有时候我甚至想把一些非常拥挤的网页粘到气球上，然后一直吹气直到页面上所有东西之前都有足够的空隙。

Put a food thermometer in a glass of water on the middle shelf, where the air temperature is most accurate. Leave it there overnight and take a reading in the morning.

将食物温度计放在一杯水中，摆在一架子的中层——温度最准确处，过夜后，于第二天早上读取度数。

You'd better leave the Windows open for a while to let the fresh air in.

你最好把窗户开一会儿，让新鲜空气进来。