to do什么是候表被动 to do有时候主动表被动，怎么区分
to do\u4ec0\u4e48\u662f\u5019\u8868\u88ab\u52a8?1. to let\uff08\u51fa\u79df\uff09\uff0cto blame\uff08\u8d23\u5907\uff09\u53ea\u7528\u4e3b\u52a8\u5f62\u5f0f\u8868\u88ab\u52a8\u610f\u4e49\u3002
\u4f8b\u5982\uff1aThis flat is to let.
\u8fd9\u5957\u516c\u5bd3\u51fa\u79df
Who is to blame for it?
\u8fd9\u8981\u602a\u8c01\uff1f
2. \u5728there be\u53e5\u578b\u4e2d\uff0c\u53ef\u4ee5\u7528\u4e3b\u52a8\u5f62\u5f0f\u8868\u88ab\u52a8\u610f\u4e49\u3002\u4f8b\u5982\uff1a
There is nothing to read.
\u6ca1\u4e1c\u897f\u503c\u5f97\u770b\u3002
There is nothing to do now.
\u73b0\u5728\u6ca1\u4e8b\u53ef\u505a\u3002
There is nothing to worry about.
\u6ca1\u6709\u4ec0\u4e48\u53ef\u62c5\u5fc3\u7684\u3002
3. \u6709\u4e9b\u5f62\u5bb9\u8bcd\u540e\u63a5\u4e0d\u5b9a\u5f0f\u4f5c\u72b6\u8bed\u65f6\uff0c\u5e38\u7528\u4e3b\u52a8\u5f62\u5f0f\u8868\u88ab\u52a8\u610f\u4e49\u3002\u6b64\u7c7b\u5f62\u5bb9\u8bcd\u6709\uff1aeasy, hard, difficult, cheap, expensive, fit, nice, good, funny, exciting, light, heavy, dangerous, comfortable, delicious\u7b49\u3002\u52a8\u8bcd\u662f\u4e0d\u53ca\u7269\u52a8\u8bcd\u65f6\u8981\u52a0\u76f8\u5e94\u7684\u4ecb\u8bcd\u3002\u4f8b\u5982\uff1a
The fish is delicious to eat.
\u8fd9\u9c7c\u597d\u5403\u3002
The ground is too hard to dig.
\u5730\u786c\u5f97\u6ca1\u6cd5\u6316\u3002
The chair is comfortable to sit on.
\u8fd9\u628a\u6905\u5b50\u5750\u8d77\u6765\u5f88\u8212\u670d\u3002
4. \u4e0d\u5b9a\u5f0f\u4f5c\u540e\u7f6e\u5b9a\u8bed\uff0c\u4e0e\u6240\u4fee\u9970\u7684\u8bcd\u6709\u52a8\u5bbe\u5173\u7cfb\uff0c\u53c8\u4e0e\u53e5\u4e2d\u540d\u8bcd\u6216\u4ee3\u8bcd\u6709\u4e3b\u8c13\u5173\u7cfb\uff0c\u8fd9\u65f6\u4e0d\u5b9a\u5f0f\u7528\u4e3b\u52a8\u5f62\u5f0f\u8868\u88ab\u52a8\u610f\u4e49\u3002\u4e0d\u5b9a\u5f0f\u4e3a\u4e0d\u53ca\u7269\u52a8\u8bcd\u65f6\uff0c\u5176\u540e\u5e94\u52a0\u76f8\u5e94\u4ecb\u8bcd\u3002\u4f8b\u5982\uff1a
Do you have anything to say?
\u4f60\u8fd8\u6709\u4ec0\u4e48\u8bdd\u8981\u8bf4\u5417\uff1f
He is a pleasant person to work with.
\u4ed6\u662f\u4e00\u4e2a\u5f88\u597d\u5171\u4e8b\u7684\u4eba\u3002
\u660e\u767d\u4e86\u5417\uff1f
hard, difficult, easy, fit, necessary, dangerous, comfortable, heavy\u8fd9\u79cd\u7528\u5728\u201csth/sb be+\u8fd9\u4e9b\u5f62\u5bb9\u8bcd+to do\u201d\u8fd9\u79cd\u60c5\u51b5\u7684to do\u662f\u88ab\u52a8\uff0c\u6bd4\u5982You are so heavy to lift up.\u4e3e\u8d77\u4f60\u6765\u771f\u91cd\uff08\u4f60\u88ab\u4e3e\u8d77\u6765\uff09\u3002
to let, to blame, to rent, remain to do\u7b49\u5e38\u7528\u4e3b\u52a8\u7ed3\u6784\u8868\u793a\u88ab\u52a8\u542b\u4e49\u3002\u6bd4\u5982I am to blame.\u8fd9\u4e8b\u513f\u602a\u6211\uff08\u6211\u662f\u88ab\u602a\uff09\u3002
sb/sth+have/has+sth to do.\u4e5f\u662f\u8868\u793a\u88ab\u52a8\u3002\u6bd4\u5982I have so much work to do.\u6211\u6709\u90a3\u4e48\u591a\u6d3b\u8981\u5e72\uff08\u6d3b\u88ab\u5e72\uff09\u3002
too...to\u548cenough\u7684\u53e5\u5b50\u4e2d\u3002\u6bd4\u5982The coat is too large to wear.\u8fd9\u4ef6\u5916\u5957\u592a\u5927\u4e86\uff08\u5916\u5957\u88ab\u7a7f\uff09\u3002The couch is not big enough for me to sit in.\u6c99\u53d1\u5bf9\u6211\u6765\u8bf4\u592a\u5c0f\u4e86\uff08\u6c99\u53d1\u88ab\u5750\uff09\u3002
主语＋be＋adj.＋to do的结构中，动词不定式常用主动结构表被动含义。
to do和doing的区别为：意思不同、用法不同、侧重点不同。
一、意思不同
1、to do：待办事项。
2、doing：所做的事，发生的事。
二、用法不同
1、to do：动词不定式，为非谓语动词。在英语语法中，动词不定式是指动词中的一种不带词形变化从而不指示人称、数量、时态的一种形式。它之所以被称做不定式，是因为动词不被限定，或者说不被词形变化所局限。不定式属于非谓语动词形式。
2、doing：动名词，指的是动词ing形式的一种，兼有动词和名词特征的非限定动词。它可以支配宾语，也能被副词修饰。动名词有时态和语态的变化。英语中的动名词是由动词变化而来。
三、侧重点不同
1、to do：侧重于表示想做但是还没做的事。
2、doing：侧重于表示正在做的事。
5. 主语＋be＋adj.＋to do的结构中，动词不定式常用主动结构表被动含义，这些表语形容词有hard, difficult, easy, fit, necessary, dangerous, comfortable, heavy等。例：
The problem is hard to solve.
The chair is comfortable to sit on.
I find the water in the well fit to drink.
7.有些不定式，如：to let, to blame, to rent, remain to do等常用主动结构表示被动含义。例如：
The taxi is to rent.
Much remains to find.
Who is to blame for starting the fire?
The house is to let.
8. “主语+have / has + 名词+ to do”结构，也用主动结构表被动含义，此时主语与to do 存在逻辑上的主谓关系，to do 与宾语存在逻辑上的动宾关系。例如：
He has many problems to solve.
Mr. White has lots of things to do.
I have a room to live in.
10.在too…to…和enough to do 结构中，不定式用主动形式表示被动含义。例如： The box is too heavy to carry.
The room is not big enough to have a meeting in.
扩展阅读：什么情况被动不用be ... to do主动表被动的情况 ... to do不定式主动表被动 ... to do的三种用法 ... to do主动表被动用法 ... 什么情况下to do 表被动 ... to do表示主动还是被动 ... to be done表被动吗 ... to do什么时候主动表被动 ...
