Question

【题目】As we all know, he works ____ a doctor.

A. as B. on C. on D. as

Answer 1

【答案】D

【解析】句意：众所周知，他是一名医生。as we all know众所周知，as引导状语从句；as a doctor作为一个医生，as介词，作为, 后跟表示身份、职业的名词。故选：D。