has many advantages. In the first place,

                                              Second,   

                                           . Third,       

                                  . For all these advantages, it is really worthwhile to                                    .

  However just as everything has two sides, there are some disadvantages in                                         .

The most serious problem is                                

                                . Besides,               

                                                       .

  Therefore, given an opportunity to                          ,

One must consider both sides of factors carefully before making up his mind. On the whole, it is a good thing to                    

                              , but on the other hand, one must mot lose sight for the disadvantages.

1、首先论述有利的一面

2、优势之一

3、优势之二

4、优势之三

5、由此得出的结论

6、不利的一面

7、不利因素一

8、不利因素二

9、平衡观点