订立保险合同时，保险人应主动向（）说明合同的条款内容。
A.保险代理人
B.被保险人
C.受益人
D.投保人
参考答案：D
______ in thought, he almost ran into the car in front of him.
A．Losing
B．Having lost
C．Lost
D．To lose
— will Mr Black be back to London?
—In two days.[ ]
A. How often
B. How long
C. How soon
D. How far
