Challenge (pt&pp.challenged)
n.挑战；盘问；质疑；怀疑
vt.质疑；向…挑战
vi.提出挑战，要求竞赛（或竞争）；驳斥

I like a big challenge and they don't come much bigger than this...
我喜欢大的挑战，而所有挑战中再没有比这更大的了。
The new Germany must rise to the challenge of its enhanced responsibilities...
一个崭新的德国必须迎接挑战，承担更多的责任。
I challenged him on the hypocrisy of his political attitudes.
我就他虚伪的政治观点质问他。

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Decrease (pt&pp.decreased)
n.减少，减小；减少量
vi.&vt.减少，减小

The number of independent firms decreased from 198 to 96...
独立公司的数量从198个减少到了96个。
Bank base rates have fallen from 10 per cent to 6 per cent — a decrease of 40 per cent.
银行的基本利率已从 10% 降到了 6%，降幅高达 40%。

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Significant
adj.重要的；有意义的；有重大意义的；值得注意的
n.有意义的事物；象征，标志

It is the first drug that seems to have a very significant effect on this disease.
这是第一种似乎对该病有显著疗效的药物。
Time would appear to be the significant factor in this whole drama.
时间似乎是整部剧中一个举足轻重的因素。

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Keen on
热衷于有兴趣的

His european partners are keen on emasculating hedge funds.
他的欧洲伙伴们热衷于削弱对冲基金。

剧情百科

有了目标就要有实际行动，Liza开始为自己的哈佛梦做准备。

考考你 Q&A
Q: Please use the word or phrase you just learnt to complete the sentence beblow.

1.They have been involved in a campaign of _____.
他们参与了一系列的欺骗活动。
2._____, mr obama and other democrats assailed the idea.
无论如何，当时奥巴马及其他民主党人对麦凯恩的观点进行了抨击。

A:本期答案见下期
上期答案：

1.Many genes have been identified that either increase or (decrease) appetite.
许多被发现的基因要么增进食欲要么减退食欲。
2.Anyone (keen on) modern music should not miss the opportunity.
凡喜欢现代音乐者都不应错过这次机会。