by ³

分析这个有歧义的句子,有助于我们深入了解 by 的意义和用法。大家知道,by 的最常见用法是在被动句中引出施动者:

This ability was first noticed by her father. (New Concept English, Book 4, p. 14) 她的这种能力首先是由她父亲发现的。

但是, by 也常常用来表示做某事的手段(If you do something by a particular thing, you do it using that thing.)。例如:

1. The money will be paid by cheque... 此款将由支票支付……

2. You have to express the thought by action. 你必须用行动来表达你的思想。

照此看来,你提出的句子可以有两种解释:

(a)有人用这些新方法来恐吓约翰。(Someone frightened John by the new methods.)

(b) 约翰被这些新方法吓坏了。(The new methods frightened John.)

同样,下面的句子也可以有两种解释:

Coal has been replaced by oil.

(a)煤被石油所取代。(Oil has replaced coal.)

(b)人们用石油来代替煤。(People have replaced coal by oil.)