know后面的复合宾语中不定式用不用to

倪肖丁

《薄冰英语惯用法词典》(2009)在介绍know后接带不定式的复合宾语时指出：

know用过去时或完成时，不定式以to be形式出现时，to不能省略。例如：

I have never known him to be too busy to study.

后面复合宾语中的不定式用其它动词时，不定式可带to，也可不带to（尤其英国英语中）。例如：

I never knew him (to) act without thinking.

I’ve known him (to) run faster than that.

很遗憾，《薄冰英语惯用法词典》的上述说法和例句都不够准确。

首先，在know用一般过去时的情况下，后续的复合宾语中动词不定式（无论是不是be））符号to都是不省略的。因此，《薄冰英语惯用法词典》的例句I never knew him (to) act without thinking用法失当，其中的to不宜省略。

其次，如果know用了完成体，其后不定式即使以to be形式出现，也有可能省略to。因此，其例句I have never known him to be too busy to study中，to也是可以省略的。

有关know后接含有不定式的复合宾语的问题，当代英语语法学者有相关的论述：

CGEL指出：只有当know用于完成体并具有特定语义时才跟无to不定式（Know takes a bare infinitival only in the perfect and with a special sense）例如：

I'd never known him (to) lose his temper before.

但I know him to be thoroughly reliable一句中，to不能省略。

CGEL所称know的“特定语义”指的是“亲身的、直接的经历”（a matter of knowledge based on more or less direct experience），而不是通过间接途径获得的信息。

LEG也指出：The omission of to is only possible with the perfect form of know。例如：

I've never known her (to) be late before.

I've never known her not (to) be late.

我们注意到，上述两句中不定式均以to be形式出现，但to却是可以省略的。这与《薄冰英语惯用法词典》所说的正好相反。

从其它英语书刊中见到的无to不定式用法也均与know的完成体相关。例如：

I have never known him tell a lie.  (ESI2004)

I have never known him be rude to anyone. (ESI2004)

In the most trying conditions I have never known him lose his temper. (HEG)

I have never known Tom (to) criticize anyone. （IESS）

I'd never known teachers (to) be more strict about any other school rule. (LEGP)

PEU的相关提示是：当Know 意为“经历（experience）”时，在I've never known + object + infinitive结构中不定式可以省略to. 例如：

I've never known it (to) rain like this.

PEU的上述表达似乎把省略to的用法限制在I've never known + object这种完成体的否定结构中。其实并非完全如此，因为在I have known...这种肯定句中，无to不定式也时有出现，尽管比例不高。例如：

    I have known it happen among savage peoples. （LGSWE）

    I have known John (to) give better speeches than that. (CGOEL)

在这一问题上，英国University of Essex语言和语言学系主任Andrew Radford 教授（2009）的相关说法值得关注。他认为：I have known you to have a tantrum和 I’ve never known you have a tantrum or your brother to have one either都是正确的；而I have known you have a tantrum只在某些地区方言（含英国）中出现，应被视为I have known you to have a tantrum的变体。

由此可知，动词know后跟含有无to不定式的复合宾语的惯用法是：

1. know须用于完成体形式。例如， I know her to sing on Sundays一句中，to就不能省略。

2. 只有当know表示“亲身的、直接的经历”之意时，to才可以省略。当know表示通过其它途径了解或确信该种情况时，to不能省略。例如，当你说I have (never) known Bill have a tantrum，你是在说自己（未）曾亲身见证过比尔勃然大怒发脾气。如果仅仅听他人说过，那是不可省略 to的。

3. 主要用于否定式 I've/I’d never known + object + infinitive结构中。在肯定句中通常用带 to的不定式，用无to不定式的可接受性（因地域因素而）受到一定的限制。

4. 省略to是英国英语用法，在美国英语中都用带to不定式。当know采用被动语态时也都用带to不定式。因此，无论何种情况下，用to不定式都是正确的。

5. 在符合上述条件下，不定式符号to都可以省略，与不定式是否为be动词没有直接关系。