作者：何丽琴
　　引導词what是名词性从句学习的重点，正确使用what成为学习这类从句的一大难点。近年来高考多次对what在名词性从句中的用法进行考查，下面对what的一些用法作一简析。
　　一、What引导的名词性从句
　　1.What is most important in life isn’t money. （What 引导主语从句，在从句中作主语）
　　2.Will you show me what you bought？（What 引导宾语从句，在从句中作宾语）
　　3.She is no longer what she was five years ago. （What 引导表语从句，在从句中作表语）
　　4.I don’t know what machines they are making. （What 引导宾语从句，在从句中作定语）
　　What引导的名词性从句时，what用作连接代词，可引导主语从句、表语从句、宾语从句，且在上述从句中充当主语或表语或定语或宾语，含义为“什么；……的（人、事、物）”。
　　二、What与that引导名词性从句的区分
　　分析下列从句中的what与 that：
　　1.What on earth she is is still a mystery.
　　2.That you are coming to London is the best news.
　　3.He could understand what I said.
　　4.I heard that he had joined the army.
　　5.Our plan is that we will go there once a week.
　　6.Can you show me what books you like？
　　▲小结：that 连接词，在从句中仅其连接作用，不做任何成分，无词义。
　　what 连接代词，在从句中不仅起连接作用，且在从句中充当主语、表语、定语或宾语，有词义。
　　【及时练习】
　　1._____the 2008 Olympic Games will be held in Beijing is known to the world .
　　2___we are doing now has never been done before.
　　3.____you don’t like to go to school is none of my business.
　　4.Mary has changed greatly. She is no longer _____she used to be.
　　Keys：1.That 2.What 3.That 4.what.
　　三、What与whatever引导名词性从句的区别
　　eg：1.What he is doing now is right.
　　2.Whatever he does is right.
　　从上面例句中可看出What表特指，whatever表泛指。
　　【及时练习】
　　1._____makes the shop different is that it offers more personal services.（06）
　　A. What B. Who C. Whatever D. Whoever
　　2.It is generally considered unwise to give a child _____he or she wants.
　　A. however B. whatever C. whichever D. whenever
　　Key：1.What 2.whatever
　　【小结】：what 确指某一具体的事或物，而whatever指任何事或物，并非确指具体的。
　　四、What引导的名词性从句与that引导定语从句的转换
　　★（1）He did what he could to save the drowning girl in the water.
　　He did all/everything/anything that he could to save the drowning girl in the water.
　　★（2）The town is no longer what it was ten years ago.
　　The town is no longer __the one_that was ten years ago.
　　小结：what 引导的名词性从句不含有疑问意义时，可以转换成定语从句，既：名词/the one /all/something + that 从句，从而使what 的意义更具体化。
　　【考题连接】
　　1.The other day，my brother drove his car down the street at ______ I thought was a dangerous speed.
　　2.A modern city has been set up in ____was a wasteland ten years ago. （04）
　　3. ① China is no longer ______she used to be.
　　② China is no longer the country ______she used to be.
　　4. ①______we know，an earthquake hit that area.
　　②It is known to us ______ an earth quake hit that area.
　　③______is known to us all is ____ an earthquake hit that area.
　　keys：1.what 2. what 3.①what，，②that4.①_As，②that ③_what，that
　　五、名词性从句中的what与which
　　eg：What is your favorite color？
　　Which do you like best，red，yellow or blue？
　　从上面例句中我们可以看出what 所给的范围比较的含糊，而which所给的范围比较确定。
　　【及时训练】
　　1.The books on your bookshelf are all wonderful，so I really don’t know _____ is the most interesting one.
　　2.There are so many books on sale that I don’t know ____ I should buy.
　　3. Can you point out _____two radios are the best.
　　Keys：1.what 2.which3.which
　　小结：在选择what或which时，应仔细在句中查找有无暗示范围的信息，若有用which；若没有用what。