Question

【题目】The polite boy always knocks at the door before ________ his teachers’ office.

A.checkingB.choosingC.describingD.entering

Answer 1

【答案】D

【解析】

句意：那个有礼貌的男孩进老师办公室前总是先敲门。

考查动词，checking检查；choosing选择；describing描述；entering进入。根据“knocks at the door”可知应该是进办公室前敲门，故选D。