大全649

aegeanyoung

1.        Since conscious patients often died of shock on the operating table, the invention of anesthesia was essential to the development of surgery as the invention of the propeller was to powered flight.

(A) the invention of anesthesia was essential to the development of surgery as the invention of the propeller was to powered flight

(B) inventing anesthesia was as essential for the development of surgery as the invention of the propeller was for powered flight

(C) the invention of anesthesia was as essential in the development of surgery much as the invention of the propeller had been for powered flight

(D) the invention of anesthesia was as essential to the development of surgery as the invention of the propeller was to powered flight（D）

(E) the invention of anesthesia was essential to the development of surgery, so was the invention of the propeller essential to powered flight

为什么A不对呢？

xionghuixhs

as...as....结构要完整

小腾

我觉的考察的是as..as的平行结构

A 不是平行结构啊

aegeanyoung

那如果我把它理解成AS的比较句呢？像like跟as那种 LIKE+N AS+句子，不行么？~

aegeanyoung

as是作为连词出现的 既然是连词就只能带一个句子。但是由于as所带的句

子与主句有很多相同的地方，所以可以使用加助动词省略的形式成为正确答案。

比如：
A do ***, as B do

A can *** as B can

A is *** as B and C are

补出助动词的原则是必须和主句的类型一致，而且要时态一致。

但是如果某个as结构自己就带了时间状语，那么该as结构的时态和自己带的状语

保持一致，而类型和主句保持一致。

难道是因为这样，as前面一定要加“，”才正确？~

XIAOHANMEIME

like+ N 强调 N

as +句子 强调动作

as ..as 强调 中间那堆东西

且A 与D 相比 D 更加符合ets 平衡规则所以选D咯