错例1：Canyou tell me how many students are there in this class?
正解：Can you tell me howmany students there are inthis class?
错例2：Theywere more worried about how far did they have to walk to get to thetrainstation and could they catch the train before it left.
正解：They were moreworried about how far they had to walk to get to the trainstation and if they could catch the train before it left.
1. It’s hard to decide when and where will we hold the sports meeting.
2. If you want to learn about the latest developments and discoveriesfromaround the world， you will read about them in journals and researchreportspublished in English， no matter whether are the scientists who wrotethem fromChina or Norway.
错例：It is unclear recycling can control pollution.
正解：It is unclear whether recycling can control pollution.
1. It is advertising makes us buy something impulsively.
2. There are two line charts show the unemployment rate fluctuates inChina.
3. The percentage of families have one car increased greatly.
错例：Oneof the most challenging problem is who should be responsible forlooking after the elderly people.
正解：Oneof the most challenging problems is who should be responsible forlooking after the elderly people.
1. What our modernsociety values are the personality and creativity.
2. Private car willexert adverse impacts on the environment and traffic ofthe whole society.
3. Long-distance education provides students interesting way to learn.
逗号表示句子内部的一般性停顿。两个具有独立含义的句子，在没有连词的情况下简单地被一个逗号隔开是不正确的。改正这样的错误须用句号或分号代替逗号，或用并列连词(and，but， or， so， nor， yet)连接两个句子，或用从属连词(because，as， although等)，否则会导致句子出现语法错误。
错例：Some people believe children in secondaryschool should studyinternational news as a subject， others think that’sa waste of time.
正解：Some people believe children in secondaryschool should studyinternational news as a subject. However， others think that’s a waste oftime.
或：Some people believe children in secondaryschool should studyinternational news as a subject， but others think that’s a waste of time.
1. Students should do some housework， it is goodfor them to beindependent.
2. They are far away from parents and friends， theycan deal with everythingby themselves.