新概念英语第二册：第45课课文详解及语法解析
课文详注 Further notes on the text
1.A clear conscience, (标题)问心无愧。
clear在这里的含义为“清白的”、“无罪的”，因此这个短语又可译为“清白的良心”，相当于 a good conscience，反义词为 a bad conscience(感到内疚)。
2.The whole village soon learnt that a large sum of money had been lost. 整个村子很快知道，有一大笔钱丢失了。
(1)village在这里为总称，指“村民”，the whole village指“全村的人”，后面通常跟单数动词(有时也可视为复数)：
The whole village was excited by the news.
这消息使全村的人兴奋。
(2)learn在句中的含义为“获悉”、“得知”：
I've just learnt that she was ill.
我刚刚得知她病了。
3.Sam Benton, the local butcher, had lost his wallet while taking his savings to the post office. 当地的屠户萨姆·本顿在把存款送往邮局的途中把钱包丢了。
taking为现在分词。与动名词相似，它也可以有自己的宾语、状语等。在连词while之后，现在分词短语的作用相当于一个时间状语从 句：…while he was taking his savings to the post office。现在分词这样用的前提是两个动词的主语是同一个，并且这两个动作通常是同时发生的：
He listened to music while cleaning the room.
他一边打扫房间一边听音乐。
如果是主语不一致则必须用从句：
He listened to music while I was cleaning the room.
我打扫房间时，他在听音乐。
4.Sam was sure that the wallet must have been found by one of the villagers…萨姆确信那钱包一定是被某个村民捡到了……
must用于对过去已发生的事进行推测时，后面的动词要用完成式：
When I arrived, he wasn't here. He must have left early.
我到这儿的时候他已不在了。他一定早走了。
5.it contained half the money he had lost, 里面有他丢失的钱的一半。
我们既可以说 half the money，也可以说 half of the money，它们可以互相替代，但是money前都必须有the，因为是指特定的钱。再如：
Half the bread/ half of the bread was bad.
这面包有一半已变质了。
6.In time, all Sam's money was paid back in this way. 很快，萨姆全部的钱都用同样的方式还了回来。
(1)in time可以表示“经过一段时间”或“最终”、“迟早”：
In time, he found all the books he needed.
一段时间以后，他找到了他需要的所有书。
I'll tell you everything in time.
我最终/总有一天会把一切都告诉你的。
(2)in this way表示“用这样的方式”：
You must pay attention to your spelling. In this way, you can become a good secretary in time.
你必须注意你的拼写。这样你才能最终成为一个好秘书。
语法 Grammar in use
被动语态(4)
在第10课、第21课与第34课的语法中，我们学习了用于一般现在时、一般过去时和现在完成时中的被动语态、情态助动词与被动语态的连用以及动词+宾语+不定式结构中被动语态的使用等：
That table was made in 1970(by my grandfather).
那张桌子是1970年(由我的祖父)做的。
The rooms must be cleaned today.
这些房间今天必须要打扫干净。
John has been told not to go for a walk when the weather's like this.
约翰已被告知不要在这种天气出去散步。
I never expected the thief to be arrested.
我从没有指望小偷会被逮着。
表示过去发生的动作时，被动语态还可以用于过去完成时;用于完成时的被动语态也可以与情态助动词连用：
Where the dogs ever found?
那些狗找着了吗?
Yes,they had been taken to the police station.
找着了。它们是被人带到警察局去了。(过去完成时)
I've been told to repair the gate.
有人让我来修大门。
But it's already been repaired .It must have been repaired by someone else.
但它已被修过了。肯定是其他人修的。(must+被动语态的完成式)
