Question

【题目】The window of our house _______ once a week.

A. have been cleaned B. is cleaned C. are cleaned D. are cleaning

Answer 1

【答案】B

【解析】句意：我们家的窗户一周打扫一次。考查动词时态和被动语态。once a week每周一次，用于一般现在时，可排除AD两项。主语the window是单数第三人称，同时是动词clean的受动者，需用被动语态，即is+过去分词结构，故选B。