大学英语四级考试对作文的要求是表达清楚, 语义连贯。要做到这一点, 考生必须学会过渡词的使用。过渡词(Transitional Words)是一种关系指引词, 它是连接句与句、段与段之间的纽带, 过渡词一般为副词或起副词作用的短语，另外代词、 连词也可以起到过渡的作用。
    英文作文写得是否连贯，很大程度上取决于过渡词的应用。这点既是学生写作中的薄弱环节，也是阅卷老师评分的—个重要标准。也许考生已经掌握了各类过渡词，但一到真正写作时就感到茫然，不知该如何使用，所以写出来的作文支离破碎，前言不搭后语。下面是四级作文中常用的几类过渡词及其使用场合，希望考生能熟练掌握，正确使用。
    1. 表示时间和顺序关系   这类过渡词常用来表示时间先后顺序和一系列论据的前后次序。
    after, before, first, second, then, next, finally, earlier, later, in the past, at the present, while, when, since, meanwhile, soon， soon after, temporarily, to begin with, to end with...
    2. 表示空间关系   这类过渡词经常用在说明文和描写文中，表示空间方位和顺序。
    before， behind， below， beneath， between， here,  there, where, beyond, nearby, under, above, over, below, on the right (left), in the front of, in front of, at the back of, in the middle of, at the bottom of, opposite to, next to...
    3. 表示强调   这类过渡词主要是用来强调某一个论点或论据，或事物的某个方面，在各类文体中都可以经常见到。
    again,  indeed,  actually, and, besides, perhaps, really, truly, especially, specially, to be honest, to be frank,  in particular, in addition, furthermore, naturally, of course, to repeat, what is more.... 如：
    We were tired if living in the noisy crowded city,  so we moved to the countryside. We rent a small house. In addition, we bought some old furniture. We felt quiet at home in the country. What is more,  we could enjoy fresh air and long walks every day.
    4. 表示异同关系    常用比较来指出不同事物间的相似之处, 用对比来指出不同事物的不同之处。这类过渡词经常在议论文和说明文中使用, 表示不同事物或事物不同方面的比较或对比。
    unlike, like, likewise, but, despite, conversely, nevertheless, instead, however, in contrast, in the same manner, not only...but also, on the contrary, on the one hand, on the other hand, compared with, different from, in spite of, even though, similarly, whereas...如：
    To my surprise,  my father did not criticize me. He praised me instead. Usually, my father doesn't need an assistant on his business tour. However,  he offered to take me with him this time. I guess, my father gave me this opportunity as a treat for my courageous conduct.
    5. 表示因果关系   这类过渡词经常用在推理的文章中, 表示逻辑上的因果关系。
    accordingly, so, then, thus, hence, since,  therefore,  consequently, as a result, because of, for the reason, due to, in this way.... 如：
    The people of the two countries were once on friendly terms with each other at a period of time. But for some historical reasons, the relations between the two nations were broken off. As a result, the people had been out of touch for a very long time. As time went by, the two countries decided to restore their diplomatic relationship. Accordingly,  both parties agreed to negotiations.
    6. 表示举例或例证   这类过渡词主要用来举例和例证, 在各种文章中都会经常用到。
    for example, for instance, a case in point, that is,  incidentally, as an illustration,  such as, in fact, in general,  in particular, to illustrate,  namely, in other words, that is to say, that is...如：
    Xiao Wang is a very versatile student. Besides his excellent performance in his studies, he is good at ball games, and basketball in particular. He is a good swimmer, too, and he can do in different styles, such as backstroke style and free style. He can also play two kinds of musical instruments, namely, violin and piano.
    7. 表示概要和结论   这类过渡词通常用在议论文或说明文的结尾, 表示对前面所阐述内容的概括或总结。
    in a word, in short, in brief, to sum up, on the whole, by and large, all in all, so far, therefore, thus, in summary, in conclusion, to conclude, to summarize...如：
    White-haired folks read the paper on their farmhouse porches at sunset. Worn-out wind mills stood alone in pasture... All in all,  we did not see much evidence that small-town America was vanishing.
    上面我们归纳总结了四级作文中七种过渡词的用法。同时, 值得注意的是, 一篇流畅的文章通常不只涉及到一两类过渡词。我们相信, 只要同学们能很好地掌握过渡词的用法，便不难在四级的作文考试中取得满意的成绩。