Question

有一些英语单选题目。要解析

1.The fact ____ this country spends more on its military than on education and health care combined is a serious and worrying thought．
A．where B．which C．that D．why
2.They were determined to carry out the plan at first but then we ________ persuade them to change their minds.
A. would B. could C. were able to D. had
3.Where have you been all the time? The train is about to leave. – I’m sorry I’m late, but I __________ you at the information desk upstairs. It’s lucky I thought to look for you here on the platform.
A. am waiting for B. had waited for C. waited for D. was waiting for
4.Mum, Shirley is always working late into night. What’s she up to?
---Oh, she for an important exam.
A. prepares B. has been preparing C. had prepared D. is preparing

Answer 1

1. C
句子主干是：The fact is a serious and worrying thought，从横线开始到combined结束为同位语从句，结束句子主语the fact的具体内容。
很明显，该从句不缺少任何成分，所以用that引导。

2. C
只有be able to表示“经过一段时间/努力之后能够做到某事”，即强调结果，这是它和can/could的一个较大的区别。

3. D
翻译：--你一直都到哪去了啊？火车都快开了。--对不起我迟到了。但是我（刚才一直都正）在楼上的咨询处等你。我想到到站台来找你，真是幸运啊。
解释：句意强调“刚才的时候，我正在等你”，所以用过去进行时。

4. B
翻译：--妈妈，雪莉总是工作到深夜。她在忙什么？--哦，她在为一个重要的考试做准备。
解释：B为现在完成进行时，强调动作从过去开始，一直延续到现在，而且现在还在延续。
根据题意，B为最佳答案，比D都要更好，因为后置只强调现在在准备，没有提及这一动作过去就开始了。

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