大全987-119 as比较中的省略问题

119.        Artificial intelligence emerged during the late 1950’s as an academic discipline based on the assumption that computers are able to be programmed to think like people.

(A) are able to be programmed to think like people

(B) were able to be programmed to think as people

(C) can be programmed to think as people can

(D) could be programmed to think like people（D）

(E) are capable of being programmed to think like people do

这一题目中，为什么不能将B理解为省略了动词 do 呢？to think as people do