1、as/which引导定语从句异同1、as/which引导定语从句异同as/ which 都能引导限制性或非限制性的定语从句。(1)在引导限制性定语从句时；which从句修饰的先行词是名词（词组），which可与that换用，作宾语时可省去。如：Then grow some tomatoes in one box which has plant food in the soil and some in another box which doesnt.But the studios(which)he started are still busy today, producing more and
2、 more interesting films.as从句的先行词是the same/such或被the same/such修饰；as可作主、宾、表语，一律不可省略。如：Many of the sports were the same as they are now.（as作表语）He uses the same map as I (use).他和我用的是同一份地图。（as作宾语）Such as beautiful park as is being built was designed by two young engineers.正在建造的如此漂亮的公园是由两个年轻的工程师设计的。（as作主语
3、）The printed newspaper was not such as the chief editor had expected. 印好的报纸并非如主编原来所期望的那样。（as作宾语）(2)在引导非限制性定语从句时，as,which都可作主、宾、表语，都不可省去。which从句补充说明先行词的用途、性质、状态、特征等。如：At present,the biggest nature park for milu deer in China is in the Nanhaizi Milu Park,which is about 20 kilometres south of Beijing.(
4、位置)China Daily has plenty of advertisements, which help to cutthe costs of making the newspaper.(用途)One of Charile Chaplins most famous films was“The Gold Rush”,which was made in 1925.(时间)Now, however,the maters of this great lake,which is also theWorlds deepest(over 1,740 metres), have been dirtied
5、 by wastefrom a chemical factory.(特征)which从句还可表示说话人的看法，也可对主句作意义上的补充；which=and it/ this/ that/ they;which代表的是先行词、主句或主句的一部分；which从句只能放在先行词或主句后。如：He said she could speak 4 foreign languages, which(=and it)is not true.他说她会四门外语，这是不可能的。（说话人看法，which代表宾语从句部分）比较：He said she could speak 4 foreign languages, w
6、hich(=and that)surprised every one of us.他说她会四门外语，这使我们每个人都很惊讶。（补充主句，which 代表主句）Leaves are turning yellow, which means autumn is coming. 树叶正在变黄，这意味着秋天就要来了。as也可代表先行词、主句或主句一部分。但as有“正如”的意义，其从句可放在主句前或后，如：The Nanjing Changjiang River Bridge,as we all know, was compl-eted in 1969.我们都知道南京长江大桥，它建成于一九六九年。（as代
7、表先行词）To shut your eyes to facts, as many of you do, is foolish.(如)你们许多人（所做的那样）对事实视而不见是愚蠢的。（as代表主语部分）As we know, the earth is round. 我们知道，地球是圆的。2、keep out of = keep sth.(sb.)out ofkeep out of = keep sth.(sb.)out of不使入内；不牵涉进去。Warm clothing will keep the cold out.保暖的衣服可御寒。Keep out of their quarrels.不要参与他们争吵。3、attention 短语pay attention to sth. 注意某事draw ones attention(to sth.) 引起某人的注意be worth ones attention 值得某人注意bring ones attention to sth. 叫某人注意某事