重點講解：
1. try doing sth.
嘗試做某事；
eg. You can try swimming in winter to keep healthy.
你可以試著在冬天游泳來保持健康。
eg. If you're having trouble deciding when to hold on to something and when to let it go, try doing things backward.
如果你在煩惱什么時候去擁有一些東西和什么時候放手，試著考慮做事情的結果。
2. at once
同時；一起；
eg. You can't be doing two things at once.
不能一心二用。
eg. No bank could ever pay off its creditors if they all demanded their money at once.
如果所有的儲戶同時要求提取存款，沒有哪家銀行能辦得到。
3. save time
節省時間；
eg. In the United States, many people try to save time.
在美國，許多人都盡量節省時間。
eg. We can save time if we go this way.
如果我們走這條路，就可節省時間。