请教几道GWD2语法题，thanks

欧洋彤

The greatest road system built in the Americas prior to the arrival of Christopher Columbus was the Incan highway, which, over 2,500 miles long and extending from northern Ecuador through Peru to Southern Chile.
A. Columbus was the Incan highway, which, over 2,500 miles long and extending
B. Columbus was the Incan highway, over 2,500 miles in length, and extended
C. Columbus, the Incan highway, which was over 2,500 miles in length and extended
D. Columbus, the Incan highway, being over 2,500 miles in length, was extended
E. Columbus, the Incan highway was over 2,500 miles long, extending
这题选E,  我选B  
The market for recycled commodities like aluminum and other metals remain strong despite economic changes in the recycling industry.
A. commodities like aluminum and other metals remain
B. commodities like those of aluminum and other metals are remaining
C. commodities such as aluminum and other metals remains
D. commodities, such as aluminum and other metals, remain
E. commodities, like the commodities of aluminum and other metals, remains
这题选E ， 我选C, like 不是不能举例么？

谢谢牛人们

figoliuxi

第一题这儿，over 2500miles作文extend的原因，或者说extend是over 2500miles的结果伴随状语，所以不能用and引导他们的关系，因此排除ABC，，D很容易排除，结果就选E，，实际上E的前半部分整个是插入语

第二题中自己好好琢磨吧，G中不用like举例，因为容易引起歧义，like有像的意思

欧洋彤

第一题我怎么觉得，逗号前是一个句子，逗号后是一个句子，可没有连接词啊，第一句的谓语是built 第二句的谓语是was ??
第二题正确的里边用了like 举例啊？为什么还要选

figoliuxi

第一题，built不是动词，是被动，built in the Americas整个修饰road system。。。
第二题，like表示对比，不是举例。。。