This is a sentence come from :http://www.onjava.com/pub/a/onjava/2004/04/07/wiringwebapps.html?page=2
Since Spring has built-in support for Hibernate this example DAO will extend the HibernateDaoSupport class, which allows us to easily get a reference to a HibernateTemplate, which is a helper class that simplifies coding with a Hibernate Session and handles HibernateExceptions.
There are two "which" in it,but,I can't understand what does the first "which" represent.Is it "HibernateDaoSupport class"?Or "this example DAO"?
因为Spring有Hibernate内建的支持，这个例子DAO将继承HibernateDaoSupport类，它［译者注：英语语法问题：它是指“例子DAO”还是指“HibernateDaoSupport类”？］允许我们容易取得一个到HibernateTemplate的引用，HibernateTemplate是一个帮助类，它能简化Hibernate Session的编码和处理HibernateExceptions。
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考查which的用法
［ 作者：w 转贴自：本站原创 点击数：222 更新时间：2004-4-5 文章录入：fenghe ］
考查which的用法
（一）which用作疑问代词，指上文或下文提到的几个名词中的“哪一个”。
1．_____ writer is better known in China， Charles Dickens or Mark Twain？
A．Which B．What
C．Either D．Whether
2．Dr．Black comes from either Oxford or Cambridge ，I can't remember _____ ．
A．where B．there
C．which D．that
3．There are so many kinds of tape-recorders on sale that I can't make up my mind _____ to buy．
A．which B．what
C．how D．where
4．I read about it in some book or other，does it matter _____ it was？
A．where B．what
C．how D．which
答案：1．A2．C 3．A4．D
（二）which用作关系代词，代替上文的先行词或先行句，在下文引导非限制性定语从句。
5．She heard a terrible noise， _____ brought her heart into her mouth．
A．it B．which
C．that D．what
6．Alice received an invitation from her boss，_____ came as a surprise．
A．it B．that
C．which D．he
答案：5．B6．C
关系代词which分别代替上文的先行词noise和invitation。
7．Carol said that the work would be done by October，_____ personally I doubt very much．
A．it B．that C．when D．which
答案：D。关系代词which代替上文句子的一部分the work would be done by October。
8．Dorothy was always speaking highly of her role in the play，_____ ， of course，made the others unhappy．
A．who B．which C．this D．what
9．Wilma became the first American woman who won three Olympic gold medals in tracks，_____ made her mother very proud．
A．it B．that C．which D．this
10．He was very rude to the Customs Officer，_____ of course made things even worse．
A．who B．whom C．what D．which
11．The result of the experiment was very good，_____ we hadn't expected．
A．when B．that
C．which D．what
12．John said that he'd been working in the office for an hour，_____ was true．
A．he B．this C．which D．who
13．The weather turned out to be very good，_____ was more than we could expect．
A．what B．which C．that D．it
答案：8．B 9．C 10．D 11．C 12．C 13．B
关系代词which代替上文整个主句，用以引导下文非限制性定语从句。
14．I shall never forget those years _____ I lived in the country with the farmers，_____ has a great effect on my life．
A．that；which B．when；which
C．which；that D．when；who
答案：B。关系副词when引导修饰时间名词those years的定语从句，关系代词which代替when I lived in the country with the farmers这一定语从句部分，在下文引导非限制性定语从句，when．．．which．．．形成重叠定语从句。
（三）“介词＋ which”结构引导定语从句
15．He paid the boy ＄10 for washing the windows，most of _____ hadn't been cleaned for at least a year．
A．these B．those C．that D．which
16．Recently I bought an ancient Chinese vase，_____ was reasonable．
A．which price
B．the price of which
C．its price
D．the price of whose
17．In the office I never seem to have time untilafter 5：30p．m．_____ ， many people have gone home．
A．whose time B．that
C．on which D．by which time
答案：15．D 16．B17．D
关系代词which分别指代上文先行词the windows，an ancient Chinese vase和5：30p．m．。
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关系代词 that 和which 的用法比较
中国高校指南 2004-4-9
定语从句(attributive clause)是英语语法中一项重要的学习内容?正确选择关系代词是掌握定语从句的关键?关系代词that和which均可指代先行词是事物的名词或代词,此时两者可互换,但有时that和which的使用场合并不相同?具体介绍如下:
一关系代词that的使用
1.先行词是all, anything, everything, nothing等,关系代词应用that?
That's all that I know.
2.先行词前有the only, the same, the very或no, little, much, any, every, all等修饰时,关系代词应用that?
This is the only reason that I can say.
3.先行词前有序数词或形容词最高级修饰时,关系代词常用that?
The first thing that we should do is to help him.
4.当先行词同时含有"人"或"物"时,关系代词应用that?
Can you see a man and his horse that are crossing the bridge?
5.在固定结构the same...that...; so...that...; such...that...以及it is/was...that...的强调句型中,须用that?
This is the same museum that you once visited.
6.如主句以there be开头时,关系代词应用that?
There is a house that has two windows.
7.当一个句子中含有两个定语从句时,如前一个已用关系代词which,后一个关系代词宜用that,避免重复?但两个定语从句的结构如果平行,应重复同一个关系代词?
I'll borrow a book which tells about the heroic deeds that the PLA did in the battles against the invaders.
He told me to read a book that is very short, and that is very interesting.
8. that还可引导同位语从句,which则不能?
He told me the news that they would come to see me.
二关系代词which的使用
1.非限制性定语从句中关系代词一般要用which?
She was awarded a gold medal, which the whole family considered a great honour.
2.关系代词前如有介词,关系代词须用which?如把介词移至句末,可用that (或省略)?
There's only one problem about which they disagree.
This is the book(that)she was looking for.
3.如果先行词是that,关系代词应用which?
I have that which you gave me.
4.如先行词和定语从句之间被其它较长的成分分隔,常用which?
Larry told her the story of the young airman which I narrated at the beginning of this book. (先行词为story)
5.在"those+复数形式的名词"结构中,其后的关系代词多用which?
A shop should keep a stock of those goods which sell best.
6.一个句子中如有两个定语从句,第一个定语从句用了关系代词that,第二个从句中的关系代词宜用which?但在平行结构中,应重复同一个关系代词?
This is the book that you bought which you have lost.
I have a house which is located on the hillside, which faces the south.