PREP1-90 求教~~

Archaeologists in Egypt have excavated a 5,000-year-old wooden hull that is the earliest surviving example of a "bult" boat -- in other words, a boat constructed out of planks fitted together -- and that thus represents a major advance, in terms of boat-building technology, over the dugout logs and read vessels of more ancient vintage.

A. together -- and that thus represents

B. together -- and this has represented

C. together, and it represents

D. together that was representing

E. together to represent

Answer : A

請問如何排除呢   不明白要考什麼語法觀念..謝謝

嗯..我明白了

謝謝你

请问一下，这个后面的破折号是必需的么？是不是如果后面没有破折号就算是错误的选项？

另外，怎么判断，选项

(C) together, and it represents 是错误的？

只能说C不平行了

先that,and that杀BCE,再用时态杀D,剩A

破折号我也多次想问-----到底是不是前后都要有才行?

Archaeologists in Egypt have excavated a 5,000-year-old wooden hull that is the earliest surviving example of a "built" boat--in other words, a boat constructed out of planks fitted together--and that thus represents a major advance, in terms of boat-building technology, over the dugout logs and reed vessels of more ancient vintage.

这里的结构是
            old wooden hull that is A and that thus B

That is A 做定语从句修饰 hull 没问题
        可是从逻辑意思上讲 B是由A得到的 A和B是因果关系
        这样有因果关系的A B也可以并列做hull的定语吗
             总觉得所谓并列是独立关系
        也就是去掉that is A至少可以讲的通
        例如
            sth that is red and that is wood 可是这里去掉that is A 显然不行

从逻辑上讲如果it指代old wooden hull是不是似乎C更好些
        如果it指代整句话意思
             C显然错

大家指正

因为原句是that..., and that...结构，而C选项改变了这种结构，即是改变了句子重心——改变原句的重心是GMAT语法不prefer的；

而且C中,and it represents...and引导一个独立的句子，应该要求结构和前面一个句子对称，而C做不到对称所以是错误的。

只是推测。。