英语讲义【139】切忌随便转移句子中心点

　　写英文句子时，要有明确的中心点，包括主语的人称、数目以及谓语动词的时态、语态和情态等。如果句子的中心点随便改变或转移的话，句子结构可能陷入模糊状态，使人困惑，也削弱了文章气势。

　　下面就是些有关句子中心点转移的例子：

　　⒈随便转移主语和语态，如：

　　① Cocks were heard crowing as the hikers approached the farm.

　　在一个短短的复杂句里，原本的主句主语突然变成副词从句的主语the hikers，动词语态则以被动形式出现在另一个文句里。这样的转变没有好处，也没有必要。这句话可修改为：

　　The hikers heard cocks crowing as they approached the farm.

　　这里两个主语保持中心点，一气呵成，明确多了。

　　② The tourists stayed at a holiday hotel and much of their time was spent there.

　　这里的两个并列句的主语从the tourists转入much，动词则以主动语态变成被动语态；这样做，必要吗？还是改写一下好：

　　The tourists stayed at a holiday hotel and spent much of their time there.

　　⒉随便转移人称和数目，如：

　　③ Everyone will feel happy if you enjoy good life.

　　④ Kelvin enjoys cigarette smoking, but they make his throat sore.

　　在③里，人称everyone和you不协调所以要把you改成he或everyone变成you。如果you变成he，谓语动词enjoy要变成enjoys以便动词和主语一致：

　　Everyone will feel happy if he enjoys good life. You will feel happy if you enjoy good life.

　　在④里，用they指cigarette-smoking，不符合语法规则，必须把they make改为it makes人称和数目才配合。不这样改也行，但they就要和新主语cigarettes。（不是cigarette smoking）搭挡。

　　⒊随便转移动词时态和情态，如：

　　⑤ The robber considered himself unlucky, rushed to the door, and trying to escape.

　　这句子中三个动词的时态要一致，不可以让最后一个突然改变形式，因此trying要改为tried。

　　⑥ Hold your gun tightly, take aim, and you can shoot.

　　这里的三个短句中，两个是祈使句，为什么最后一个突然变成陈述句？非改不可：

　　Hold your gun tightly, take aim and shoot.

　　You can hold your gun, take aim and shoot.

　　⑦ As I have made everything clear to him, I expected that he will let bygones be bygones.

　　显然的，这里的三个动词的时态都可以是现在式，因此主句中的expected要改为expect才行。