区别：appear，look 与 seem

IsaacZ

[思路分析]
seem 和 appear都含有“看起来似...”的意思。

appear 强调外表上给人某种印象, 有时含有实质上并非如此的意思。例如:
He appears to know more than he really does.
他看起来好象懂得很多, 其实懂得没有那么多。

seem表示有一定根据的判断, 这种判断往往接近事实。 例如:
The problem seems very complicated.
问题仿佛很复杂。
His health seems to have grown better.
他的健康似乎有所好转。
He seems to be sick, for he appears pale.
看样子他病了, 因为他面色看起来很苍白。

[解题过程]
seem,look,appear这三个词一般用作半系词，都可以汉译作“似乎”或“看上去”。
seem所表示的“似乎”或“看来”是以客观的迹象为依据的A pilot noticed a balloon which seemed to be making for a Royal Air Force Station nearby.
一位飞行员看到一个气球，好象要飞向附近的英国空军基地。
It seemed certain that this would win the prize.
这一块要得奖似乎是毫无疑问的了。

look所表示的“看来”是以视觉所接受的印象为依据的；
He looked pale and his clothes were in a frightful state.
他看上去脸色苍白，一身衣服弄得一塌糊涂。
My wife was wearing a hat that looked like a lighthouse.
我的妻子戴着一顶看起来好象一座灯塔的帽子。

appear与上两个词的含义似乎没有多大差异，但是如果要表示某种判断是由被歪曲了的印象而得出的，最好用appear。
Babies of two months old do not appear to be reluctant to enter the water.
两个月的婴儿并不显得不肯下水。
The actress is thirty-five years old,but she appears a lot younger.
那个女演员三十五岁了，但是她看上去年轻得多。

IsaacZ

三者均可用作连系动词，意为“好像”、“似乎”等，区别如下：

　　1. 从词义上看：look 指视觉印象；appear 指外表给人的印象；这两者可能是真象也可能是假象，appear 的不确定性更大一些。seem 侧重指根据某种迹象作出的推断，也不一定是事实。

　　2. 从句型搭配和用法上看：

　　(1) 三者均可后接不定式，但 look 之后一般只限于 to be (且较少见)。如：

　　正：He seems [appears，looks] to be tired. 他好像很累了。
　　正：He seems [appears] to have travelled a lot. 他似乎去过不少地方。
　　误：He looks to have travelled a lot.

　　(2) look, seem 之后可接介词 like，但 appear 之后一般不能。如：

　　He looks [seems] like a fool. 他看起来像个大傻瓜。

　　(3) appear 和 seem 不用于进行时态，但 look 有时可这样用。如：

　　正：He looks [is looking] well. 他看上去气色不错。
　　误：He is seeming [appearing] well.

　　(4) 三者均可用于 it 开头的句子，且三者之后均可接以 as if 或 as though 引导的从句，另外 appear 和 seem 之后还可接 that 引导的从句。如：

　　It looks [seems，appears] as if he has lost interest in his job. 看来他对自己的工作已失去了兴趣。
　　It seems [appears] that he is very tired. 他似乎很累了。

　　注：后接 that 从句时，有时可用 so，not 代之。如：

　　A：Are they reliable? 他们可靠吗?
　　B：It seems [appears] so (not). 似乎是可靠的(不可靠)。

　　另外，比较以下同义句型：

　　It seems [appears] that he is ill. ＝He seems [appears] to be ill. 他似乎病了。

IsaacZ

一、含义上的差异

appear 是指根据事物的外表表象做出判断的，但实质上并不一定如此；seem是表示说话人主观上的判断，暗含有一定的根据，往往接近事实的判断；look是根据视觉印象而得出的判断，实质上也可能如此。例如：

She is fifty but she appears young . 她五十岁了，但看起来很年轻。(其实并非如此)

Se seems young . (I think he is rich .) 她看起来很年轻。(根据个人的主观判断而推断出)

She looks young . 她很年轻。(从他外表可出感觉出)

二、用法上的差异

1. appear，look，seem 后均可带名词、形容语、to be 结构。

The man who came yesterday appeared / seemed / looked an hounest man . 昨天来的那个人看来是一个诚实的人。

My brother appeared (to be) happy when he heard from sister . 当我弟弟收到我妹妹来信时，似乎很高兴。

2. look 可用于进行时，而 seem , appear 一般不能。如：

He is looking very happy. 他现在看起来很高兴。

3. appear 和 seem 之后可接动词不定式的一般式、完成式以及其他形式，而 look 之后除了能接to be 结构外，不接其它动词不定式形式。

She appeared to agree with you. 他好象同意你的意见。

They don’t seem to have read this novel. 他们好象没有读过这本小说。

4. look , seem 能与介词 like 构成习语，意思是“看上去象”，而 appear 却不能。例如：

It seems like years since I last saw you . 自从上次见到你后，好象很久没有见到你了。

He looks like a farm.他看起来象个农民。

5. seem , look 后均可接 as if , as though 引导的表语从句，从句中既可用陈述语气也可用虚拟语气，而 appear 则不能。例如：

It seemed / looked as if he had been to Beijing. 看起来他去过北京。

（IsaacZ注：此点与2楼所述不同，请到www.yahoo.com搜索（带引号）"appear as if" 求证，appear可变换多种时态，前面试加it）

6. appear 和seem 均可接 that 引导的从句，而 look 不能。

It seems / appears that we won’t finish this work today. 我们好象今天完不成这项工作。

7. appear 和 seem 可用于there be 结构中，而 look 不能。如：

There appears to have been an accident . 好象出了一次事故。