—Recent pressure at work may ______ his behavior.
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.
54. Because of the year 2008 Olympic Games, the American corporation board of trustees(董事会) decided to set up a Chinese _____ in Beijing.