D
The Leaning Tower of Pisa has gone against the laws of gravity for seven and a half centuries.Every year，on June 19th，a professor from the University of Pisa climbs to the bell tower and measures the increase in the slant(倾斜) with special instruments.And every year the professor makes the same report：the tower has learned a bit—about an inch more.Last summer(the year of 2004)，the 125foothigh tower was leaning an incredible 15 feet out of line.Scientists say that unless a way is found to stop the slant，the tower will collapse in less than 80 years.
The tower is leaning because the soft soil of Pisa will not support it.Its foundation is sinking into the soil at an angle，causing the tower to lean.Since a slight shake could make the foundation loose，the ringing of the tower's bells was forbidden in 1959.And trucks are not allowed to pass in the neighborhood of the tower for this same reason.
47.This passage is mainly about ________.
A.a famous tower that leans
B.a plan for saving the tower
C.the history of the Tower
D.the cause of the tower's slant
解析 主旨大意题。文章主要介绍塔的一些情况，而不是关于a plan for saving the tower，更不是单纯说明the cause of the tower's slant。
答案 A
48.This summer the tower may be found to be in the slant by ________ according to the passage.
A.more than one inch B.exactly one inch
C.more than fifteen feet D.exactly fifteen feet
解析 推理判断题。见第一段第三句、第四句“And every year...about an inch more”，“Last summer...15 feet out of line”可断定“this summer...of...more than fifteen feet”。
答案 C
49.Truck traffic has been forbidden in the neighborhood of the tower ________.
A.to protect all the visitors
B.to prevent the bell in the tower
C.to protect the foundation
D.to keep the soil at the tower
解析 推理判断题。见第二段最后两句。
答案 C
50.According to the way it is written，this passage is more like ________.
A.a funny history story B.a serious tour advertisement
C.an exciting announcement D.a common science report
解析 推理判断题。根据全文可知D为最佳答案。
答案 D
