41.It _____ 30 years since I got to know him in Wuhan.

41.It _____ 30 years since I got to know him in Wuhan.
A.is B.was C.had been D.being
42.Having been operated _____ twice for the disease,she was so weakened that she could barely stand up.
A.at B.with C.on D.in
43.It is well known that lung cancer is caused at least ____ by smoking too much.
A.in spite of B.in detail C.in addition D.in part
44.Hainan Island attracts tourists ____ in winter _____ in summer.
A.neither …or B.not only ….but also C.hardly… when D.no sooner ..than
45.His illness is incurable.It’s a terrible thing for him to know _____ the doctors are not able to save his life.
A.what B.that C.which D.where