ttgwd4-17

Q17:

The steel industry has changed radically over the last two decades, as large, integrated companies such as Bethlehem Steel once conducted operations from mining at one end of the process to shipping at the other have greatly downsized, or in some cases shut down altogether.

1. as large, integrated companies such as Bethlehem Steel

2. as large, integrated companies, such as Bethlehem Steel, that

3. with large, integrated companies, such as Bethlehem Steel, that

4. while large, integrated companies, such as Bethlehem Steel, that

5. and large, integrated companies such as Bethlehem Steel

i want to know why choise D is incorect?

ding!

顶~同样疑问

是选B么？

我觉得as这里有因果作用

up!

不明白

WHILE和AS,在这句话中什么意思

请问as在这里引导什么从句阿？好像也不是时间状语从句阿。