Question

【题目】---How often do the students play sports? --- .

A. Since last night B. For two hours C. A month ago D. Once a day

Answer 1

【答案】D

【解析】句意：——学生们多久做一次运动？——一天一次。Since last night自从昨天晚上；for two hours两个小时，a month ago一个月前；once a day一天一次；根据how often可知此处表示频率，故选D。