例证是为了证明主题而存在的。当主题为理论性或概述的论点时，就需要通过举例或例证来加以支持，以说服听者，同时要注意逻辑严密。例如：In many countries, cigarette is restricted in many ways. For example, in Britain, cigarettes are not allowed to be advertised on TV or radio.
因果法是用来解释“为什么”的问题。我们可以根据一个结果去推导其原因，要以事实和证据为根据，前后过程要合乎逻辑和常理。例如：“你为什么考研”？Why do you choose to take the postgraduate exams?There are several reasons why i took the postgraduate exams.Firstly, I have been deeply impressed by the atmosphere here. The second reason is I want to be a social worker. Thirdly, I think further study is still urgent for me.
常用因果联系词： because of, because, since, seeing that, the reason why, on account of, due to, thus, hence, therefore, accordingly, consequently, so that, as a result of, in consequence of, result from, lead to, so... as to, owing to, to have an effect on, for the reason, in this way, thanks to等。
but, however, yet, instead, whereas, otherwise, nevertheless, unfortunately
定义法可以用来阐述“是什么”的问题，即用一段话来解释说明某个抽象的概念或具体事物的性质、特征、用途、原理等。例如：What is honesty? 我们可以用如下形式来展开论述：Honesty means telling the truth and being fair and upright in action. It is a good virtue. One who cheats is dishonest. Those who gain fortunes not by hard labor, but by other means are dishonest.
The causes for …are as follows…
…may be classified according to /on the basis of /depending on…
first, second, third…last; firstly, secondly, thirdly… finally; to begin with, what’s more, in the end; first of all, then, next, moreover, furthermore…, in the first place, in the second place, last but not least
cause, result in, lead to, produce, bring about, contribute to, based on, because, since, now that, therefore, thus, consequently, owing to, due to, through, because of, on account of, as a result, as a consequence
常用关联词汇： what is..., to be defined as, the definition of ... is, to be used to describe, this means, be explained, state that, in other words, namely等。
2. As we can easily see from the above graph, the figure of …has nearly decreased/increased …times, compared with…
例证常用的关联词： for example, for instance, for one thing, for another, to illustrate, one example is, first, second, furthermore, besides, in addition, moreover, finally,a case in point, as an illustration, incidentally, namely等。
3. From… to …, great changes have taken place in…
There are some similarities/differences between…
Only through these measures can we hope to solve the problem。
1. One of the most serious problems our country is faced with nowadays is …
4. As is known to all, …(谚语或名言). A case in point is that…
1. When it comes to…, different people hold different views. Some argue that…, while others believe that…
…may be divided into…
arrange in two/three categories, be classified into a number of groups, fall into the following kinds, be put into several groups, consist of
There are many causes/reasons for…. Firstly, …, secondly, …, thirdly,…