连接文中上下句的词汇，即所谓的信号词，往往表示句子间的关系，有助于考生把握各细节间的相互关系。这些词主要有：
A、表示顺承和递进关系
例词：also, apart from, besides, moreover, furthermore
例句：The Victorian style of heavily ornamented interiors prevailed in middle-class homes in England and the United States during the latter half of the 19th century. Moreover, in both countries, techniques of mass production promoted the use of reproductions in many different styles.
B、表示对比与转折关系
例词：but, however, though, although, yet, nevertheless, on the other hand
例句：Education is the passport to modern life, and a pre-condition of national prosperity. But more than a quarter of the world‘s adults cannot read or write, and more than 100 million young children are deprived of even a primary school education.
C、表示相似关系
例词：like, as, likewise, similar to, in the same way
例句：Like other ways of generating electricity, wind power does not leave the environment entirely unharmed.
D、表示时间先后关系
例词：now, later, before, after, since, when, first, second, next, at last, eventually, finally
例句：As the volunteers began to fall asleep, the electrodes detected the slow rolling eye movements which could be seen easily through their eyelids. Soon after, the volunteers fell deeper into sleep and their eyes became still.
