fluctuate v.波动；变动

同alternate, wave

Some investors panic when stock prices fluctuate wildly.

当股票价格大幅波动时,一些投资者便开始恐慌起来。

gainsay v.否认

同deny, disagree

There was no gainsaying the astronomer's knowledge about the planets.

这位天文学家对于行星的知识是毋庸置疑的。

*astronomer n.天文学家

hybrid n.混种；混血儿

同half-breed, mixture

Scientists have developed a hybrid of rice that is more resistant to diseases and insects.

科学家已开发出一种对疾病与虫害更具抵抗力的杂交水稻。

idiom n.习语；惯用语

同expression, phrase

When studying a foreign language, idioms are often the most difficult thing to learn.

学习外语时，习语常是其中最难学的部分。

Inappropriate adj.不适合的

同unsuitable, improper, unfit, incongruous

This movie is very violent and is inappropriate for children to watch.

这部电影暴力倾向严重，不适合儿童观看。

innocuous adj.无害的

同harmless, inoffensive, vapid, insipid, innocent

I don't understand how such an innocuous children's book could cause such an uproar.

我不明白为何这本对儿童无害的书竟会引起如此的骚动。

*uproar n.骚动

jerk n.拉扯

同twitch, pull, yank

I felt a jerk on my sleeve, then realized it was just a tree branch.

我觉得有人拉我的袖子，后来发现只不过是树枝而已。

laconic adj.简洁的

同concise, compact, pithy, short, succinct

Henry's date was very laconic, only saying two sentences the entire evening.

亨利的约会十分简洁，整晚他只说了两句话。

lumber n.木材

同wood, timber, logs

A lot of lumber was needed to build the Smith's new house.

建造史密斯的新家需要大量木材。

magnify v.放大

同enlarge, expand, amplify, augment

Danny used a lens to magnify the tiny insect.

丹尼利用镜片来放大那只微小的昆虫。*lens n. (pl.)镜片