题目内容
【题目】Before you enter the room, you need to knock ________ the door politely.
A. for B. about C. with D. at
【答案】D
【解析】
句意：在你进入房间前，你需要礼貌地敲门。短语knock at/on the door是固定搭配，意为“敲门”，knock不与for/about/with等介词搭配，故选D。
练习册系列答案
相关题目
题目内容
【题目】Before you enter the room, you need to knock ________ the door politely.
A. for B. about C. with D. at
【答案】D
【解析】
句意：在你进入房间前，你需要礼貌地敲门。短语knock at/on the door是固定搭配，意为“敲门”，knock不与for/about/with等介词搭配，故选D。