为了下文阐述思路清晰，我先给大家列两个基本公式：主动句：X does Y. 被动句：Y is done by X. X=动作执行者，施动者 Y=动作承受者，受动者 当然，这里的does和is done是各种动词和时态的代表。总的来说，被动语态的使用与施动者X、受动者Y、话题语境以及谓语动词都有关系。接下来我就以这个思路作为主线来讨论被动语态的各种用法。

两类被动句：“有 by”和“无by” 如果学过《新概念英语》第2册，那你对下面这篇短文应该不会陌生： 下面我就通过详细解读这篇短文来向大家揭示被动语态的用法。首先给出每句话的翻译： We have an old musical instrument.(我家有件古乐器。)It is called a clavichord.(被称作古钢琴。) It was made in Germany in 1681.(是1681年德国造的。) Our clavichord is kept in the living room.(我家这架古钢琴放在起居室里。)It has belonged to our family for a long time.(我家很早以前就有这件乐器了。) The instrument was bought by my grandfather many years ago.(是我祖父很多年以前买的。) Recently it was damaged by avisitor.(可它最近被一位客人弄坏了。) She tried to play jazz on it!(她试图用它来弹奏爵士乐。) She struck the keys too hard and two of the strings were broken.(她在按压琴键时用力过猛，损坏了两根琴弦。) My father was shocked.(父亲十分生气。) Now we are not allowed to touch it.(不许我们再动它。) t is being repaired by a friend of my father's.(父亲的一位朋友正在修理这件乐器。)

上面的句子中，除了1、5、8以及9的前半句(She struck the keys too hard)，其他句子都是被动句。这些被动句可以分为两大类： 一类是不含施动者的被动句(以Y is done来标记)： It is calleda clavichord. It was madein Germany in 1681. Our clavichord is keptin the living room. ...two of the strings were broken. My father was shocked.Now we are not allowedto touch it. 另一类是包含施动者的被动句(以Y is done by X来标记)： 6. The instrument was bought by my grandfathermany years ago. 7. Recently it was damaged by a visitor. 12. It is being repaired by a friend of my father ' s. 这类被动句通过介词by引出施动者，如my grandfather、a visitor和a friend of my father's。 显然，一个带有by短语的被动句，在去掉by短语之后就会变短。因此，有语法家把一类被动句称为short passives，字面意思就是“短被动句”，而把第二类被动句称为long passives，字面意思就是“长被动句”。不过，我不愿意用这样的术语，因为它们容易引起误解。我就直白地把没有by短语的被动句称为“无by被动句”，而把带有by短语的被动句就称为“有by被动句”。此外，还有一类我称之为“非by被动句”，就是用by之外的介词来引导施动者。