While ________ for the bus at the bus station, I met an old friend of mine whom I haven't seen for 10 years.
A.being waited B.waiting C.having waited D.waited正确答案B
While ________ for the bus at the bus station, I met an old friend of mine whom I haven't seen for 10 years.
A.being waited B.waiting C.having waited D.waited正确答案B
