雅思大作文主体段落一般由主题句和扩展句构成。主题句一般放在第一句，是段落核心，用来概括全段内容。主题句分为笼统主题句和具体主题句。笼统主体句的作用是引出下文，点明方向，具体主题句则概况下面内容的核心主题。仅有主题观点是不够的，还要对其进行论证，也就是围绕主题进行论证，对其进行说明、叙述、举例及论述。
一、举实例论证。
有些考生在开头提出观点之后，就不知道该如何继续下去。这种情况下，考生可以举实例论证，举例是我们解释论证一个观点最好的方式，也是最有说服力的。
Although sticking to one s goal is key to success, sometimes one should be ready to give up. Napoleon s story is a case in point. After Napoleon succeeded in seizing the crown of France, he should have been satisfied with his achievement. But he did not. He went on to conquer the whole Europe. Then after he succeeded in ruling almost the whole Europe, he should have given up this ambition to expanding his empire. But he did not. He went on to invade Russia and there he suffered a total defeat. Later he was sent into exile and died in a lonely island。
本段引用了拿破仑的事迹来加以论证。拿破仑是家喻户晓的人物，而且最后决定拿破仑及其帝国命运的滑铁卢战役也是大家都知晓的。通过这个例子来说明在适当的时候学会放弃是很有说服力的。在举例时，最好选择一些大家都知晓的，这样才能更有说服力。当然考生也可以用自己的亲身经历来加以论证。
The second reason for my propensity for outdoor activities is that they can build my mind greatly. In sports, one must learn to struggle for the victory, learn to fight with no matter what is left in his body. And one must learn to stick to one s own confidence and hope, no matter how little the hope may be. And one must learn to accept failure, learn to start again after failure. Long-running and mountain climbing contribute much to this kind of spirits. I will never forget the feeling when I raced to the final line first in a 300-meter running. I could hardly breathe in the last 100 meters. My lungs ached and my legs weighed tons, but there was still one runner in front of me. I gave all my strength to move one foot ahead of the other. When I surpassed him, he gave a cry of surprise, I won at last and I learned much from the race。
文章在提出主题句后，先是加以论述，然后用长跑和爬山作为例子。最后又用自己的亲身经历和感受来论证室外活动可以增强一个人的毅力。
二、用一些研究、调查、发现、科学家及权威人士的观点或组织机构的研究结果加以论证，并引用数据作为支撑。此论证方法的好处就是比较权威客观，更有说服力。
If people move to live in different places, they will have more opportunity for improving their lives. According to a survey conducted by the Chinese Academy of Social Sciences, 55% of urban Chinese had changed their living place at least once in their lifetime by 2000, an increase of 30 percent as compared with that of 2 decades ago. Chinese sociologists agree that this trend is most likely to continue with the development society. Statistics indicate that people who moved at least once in their lifetime enjoy a much higher living standard than those who never moved。
本段先是引用中科院的调查数据加以论证，然后用某些专家和数据继续加以论证。有一点值得注意，很多考生并不知道真实的数据，考试中往往是自己的发明创造。所以没有把握的情况下，尽量不要去写那些众所周知的人或者机构，可以模糊地用某个机构或某个学者，数据上也千万不要太夸张，只要能达到有力够论证自己的观点即可。
