单项选择题
At the moment the machine（）at full speed.
A. ran B. was running C. had been running D. had run
单项选择题 Seldom（）my boss in such a good mood since I came to work in this company.
单项选择题 I haven’t seen my neighbors for over a week. They（）on a trip abroad.
单项选择题 To get into the habit of smoking means（）one's own life short.
