英语常用并列连词，如：and, but, so, yet, for, nor, or, not only:..but also, either …or或neither…nor等连接两个或几个同等成分，这种结构称为并列结构。连接的同等成分可以是动词的宾语、介词短语或名词的定语等。
    
    例1 In general, the tests work most effectively when the qualities to be measured can be most precisely defined and least effectively when what is to be measured or predicted can not be well defined. (1995年真题)
    
    例2 Astrophysicists working with groundbased detectors at the South Pole and balloon borne instruments are closing in on such structures, and may report their findings soon。(1998年真题)
    
    例3 It is not that (不是)the scales in the one case, and the balance in the other, differ in the principles of their construction or manner ofworking; but that (而是) the latter (后者) is a much finer apparatus and of course much more accurate in its measurement than the former (前者)。(1993年真题)