It has been found that certain bats emit squeaks and by receiving the echoes, they can locate and steer clear of obstacles -- or locate flying insects on which they feed.
emit 放射，发射（声音、光线、信号）
- The factory emits smoke into the air every day.工厂每天向空气中排放烟雾。
- Radioactive materials emit radiation.放射性物质会释放辐射。
- He emitted a loud sigh of relief.他松了一口气。
| emit e(out)+mit(send) | The volcano suddenly emitted a huge cloud of smoke.火山突然喷出一团浓烟。 |
| submit sub(under)+mit | Please submit your report before Friday.请在星期五之前提交报告。 |
| transmit trans(across)+mit | The US Open will be transmitted live via satellite.美国网球公开赛将通过卫星直播。 |
| omit o(ob,away)+mit | He omitted an important detail in his speech.他在演讲中遗漏了一个重要细节。 |
| vomit vo(eat)+mit | The child vomited after eating spoiled food.孩子吃了变质的食物后呕吐了。 |
steer clear of 避开，躲开(= avoid … = get around … )
- We tried to steer clear of political issues.我们尽量避免涉及政治问题。
- I steered clear of the main roads where I might be recognized.我避开了可能被认出的主干道。
- He always steers clear of trouble.他总是远离麻烦。
feed on 以…为食
- Cows feed on hay.奶牛以干草为食。
- Deer feed on grass and leaves.鹿吃草和树叶。
- These birds feed on small insects.这些鸟以小昆虫为食。
- However, certain other species on which the larvae feed do not harbor the bacterium. 然而，幼虫所食的某些其他物种却不存在这种细菌。
| prey on 动物以…为食 | Owls prey on mice.猫头鹰捕食老鼠。 |
| live on 人以…为主食 | Many people live on rice in Asia.亚洲许多人以大米为主食。 |
This echo-location in bats is often compared with radar, the principle of which is similar.
compare A with / to B 将A与B比较
- People often compare the heart to a pump.人们常把心脏比作泵。
- Let's compare our results with theirs.让我们把结果和他们的比较一下。
- He compared her voice to music.他把她的声音比作音乐。
| contrast A with B 对比A与B（强调不同） | It’s interesting to contrast European culture with Asian culture.对比欧洲文化与亚洲文化是很有趣的。 |
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名词 + 介词 + 关系代词 引导非限定性定语从句(修饰先行词一部分或者相关部分)
- He has two sons, one of whom died in the war.他有两个儿子，其中一个死于战争。
- The speaker posed four questions, the answers to which proved very illuminating.演讲者提出了四个问题，其答案被证明非常有启发性。
- The most valuable find was the ship’s log book, parts of which were still readable. （不修饰先行词本身，而是与先行词相关的部分）