今天，托福君打算上来谈谈独立写作主体段的写法。主体段的写法嘛，肯定是上来就得先亮出你的论点(姿势要简洁有力，忌拖泥带水)，然后用一两句话引申和解释一下这个论点(这里有套路)，再然后就是举例(请用3句话搞定一个栗子)。如果按照这个套路来写的话，一个主体段大概能凑出120-150字左右，是不是够啦?

　　通常，主体段的第一句话，也就是论点，还是比较好写的，因为在构思阶段，你已经确定好了自己的2到3个主要论点是不是?那么问题应该是，写出一个论点后，该怎么对它进一步elaborate呢?抛出论点然后直接举例的做法是万万不能的，一来这样太缺乏论证和细节，二来字数也不够哇。

　　今天这篇文章，就来写一写怎样elaborate论点，或者说怎样论证你的观点。论证的方法除了举例论证外，还有很多，比如因果论证、类比/对比论证、转折论证、让步论证、假设论证等等。事实上，逻辑清晰合理是主体段压倒一切的首要要求。

　　一、假设论证

　　说到假设，恐怕大家第一个想到的就是if，请看下面这个高分范例的写法：

　　Taking a wide variety of subjects provides a common core of knowledge for all educated people.(论点) If students limited their courses to their major fields of study, they would not have a broad view of the world. Their vision would be very narrow and they would not be able to exchange views with others whose education had been limited to the study of a different field.

　　那么除了if之外，还有哪些词可以用来表达假设逻辑呢?

　　providing that

　　unless

　　as long as

　　on condition that

　　no matter how

　　造几个句子吧：

　　1、如果你在一小时内能还我，我就把字典借给你。

　　You can borrow my dictionary providing that you return it in an hour.

　　2、如果你分数不够漂亮，你就上不了大学。

　　You cannot go to university unless you have good grades.

　　3、如果我们随便丢弃东西，环境污染就会越来越严重。

　　Pollution will get worse as long as we continue to live in a throwaway society.

　　4、如果钱被用来投资教育和医疗，那么很多发达国家就愿意放弃收回那些第三世界的借贷。

　　Many developed countries are willing to waive the Third World debt on condition that the money is reinvested in education and medicine.

　　5、很多国家就算再努力也无法改变财政赤字了。

　　Some countries will never be able to rectify their deficits no matter how they work hard.

　　二、因果论证

　　因果逻辑词实在是太多了，大家都该信手拈来了吧。

　　例：

　　Serious TV shows can be used as supplementary teaching tools.(论点) For many American students, once they get back home, the first thing that they do is to turn on the television. Therefore, recommending to their students serious TV shows that contain reflections on history, economy, science or social justice can really help teachers extend teaching into their students’ leisure time.