我们常说，良好的开端等于成功的一半。做事如此，作文也是如此。所以我们颇有必要在作文的开头花一番心思。

　　在写议论文时，你通常以什么样的方式开头呢？最简单也最常用的可能就是开门见山法。也就是说———直截了当地提出你对这个问题的观点，点出文章的中心思想。

　　I……has both advantages and disadvantages.……既有利又有弊。例如：

　　1.Obviously television has both advantages and disadvantages.

　　2.Living in a city has both advantages and disadvantages.

　　3.Com pared with cars,bikes have their advantages and disadvantages.

　　举一反三：

　　1.Although computers bring people a lot of convenience,they have many disadvantages.

　　2……has many advantages.For example,……However,just as every coin has two sides,……has its disadvantages.（本例将利弊分开讲，转折过渡自然。just as every coin has two sides也很值得背诵。）

　　II……play（s）an important role ／part in…………在……中扮演重要角色／起重要作用。例如：

　　1.Computers play an important role in science and technology.

　　2.Computers play a more and more important role in our life.

　　Computers play an increasingly important role in our studies.

　　3.Education plays an important part in developing our mind.

　　4.Addiction to alcohol and drugs play a role in homelessness.