Doris' success lies in the fact _______ she is co-operative and eager to learn from others.(2006年上海春季高考题)
49. ____ and friends should be few but good. (prov.)
50. John is on the bottle again. This sentence probably means _____.
51. --- Who is at the _____ of all this trouble. --- I don’t know.
52. I shall walk with you to the bottom of the road. The underlined part means ____.
53. --- Please tell me how to work out this maths problem. --- Use your ______ , then your find a way.