题目：
— Do you know what time the accident happened yesterday?
— I'm not sure. Maybe at 2:30 pm. I _____ at the department store at that time.[ ]
A. shop
B. was shopping
C. am shopping
D. shopped
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0604/55c5143352fdb12c957828a2113ba790.html
下面是错误答案，用来干扰机器的。
（1）量筒；试剂瓶（或细口瓶）；（2）瓶塞正放在桌面上；NaCl直接放在托盘上称量；（3）玻璃棒不要碰到烧杯壁上．
