key
单词辨析：
主要指习题、难题等的答案。
Check your answers in the key at the back of the book.
用书后的解答核对答案。
I don't know the key to the puzzle.
我不知道这个谜语的谜底。
指试题、竞赛题等的答案，也可指某一问题的解决办法。
the answer to rising crime
解决犯罪率上升问题的办法
What is the answer to question 5?
第五题的答案是什么？
Having all the figures she figured out the answer quickly: it was 249.
有了所有这些数字，她很快就解答出来了，答案是249。
指解决问题、难题的办法，也可指练习题、竞赛题等的答案，常可与 answer 换用。
It seems to me the best solution/answer.
依我看这似乎是最好的解决办法。
It's difficult to find a solution/an answer to the problem.
很难找到解决该问题的办法。
The solutions/answers to the problems are on page 258.
题目的答案在258页上。
语气较强，指对于某人或某事成功或继续存在是至关重要的。
It is vital to keep promises.
遵守诺言非常重要。
These measures have played a vital role in restoring the economy.
这些措施在恢复经济过程中起到了极为重要的作用。
指对将来发生的事而言十分重要的。
These talks are critical to the future of the country's overseas investment.
这些谈判对该国海外投资的前景至关重要。
It is absolutely critical for them to know the truth.
他们知道真相是至关重要的。
指作用十分重要或不能缺少的。
Who makes all the key decisions on foreign policy?
外交政策上所有重要的决定都是谁作出的？
Their research centred on the key factors of the solution to environmental pollution.
他们的研究集中于解决环境污染的关键因素上。
相关例句：
At these conventions, executives fraternized with the key personnel of other banks
在这些集会上，主管们和其他银行的重要人员友善往来。
The key focus of the marketing mix will be on price and distribution.
营销组合的重点将放在价格与配送上。
In the light of this information it is now possible to identify a number of key issues.
根据这一信息，现在有可能弄清楚几个关键问题了。
Education and training is the key that will unlock our nation's potential.
教育和培训是发掘我们国家潜力的关键。
She reached for her coat and car keys.
她伸手拿外套和汽车钥匙。
What key events influenced the energy situation in 1979?
是哪些关键性事件影响了1979年的能源状况？