单项选择题
W: Jack, Where have you been? You’re supposed to get here an hour earlier.M: Sorry, Aunt Ruth, but I’m afraid I don’t know my way around Manchester yet.Q: What can we learn about Jack from this conversation?（）
A．Jack is new in Manchester.B．Jack was in a traffic jam just now.C．Jack arrived an hour earlier.D．Jack went to Manchester an hour ago.
单项选择题 下面各项既可以作为安全生产从业人员的权利,又可以作为其义务的是( )。
单项选择题 休戚相关：唇齿相依（）
单项选择题 【C1】（）
