三：概括大意和完成句子：

　　23題答案：B

　　24題答案：A

　　25題答案：F

　　26題答案：D

　　A. The Relapsing Form of MS

　　B. The Definition of MS

　　C. The Cause of MS

　　D. The Development of MS

　　E. The Treatment of MS

　　F. The Primary Progressive Form of MS

　　27. MS affects the young adults of nerve cells between the body and ______.

　　答案：B

　　28. An MS patient can feel fine for years without being affected much by the ______.

　　答案：C

　　29. 10-15% of MS patients are diagnosed as having _______.

　　答案：E

　　30. Young adults might have a higher chance of developing the disease than_______.

　　答案：A

　　A. the elderly people.

　　B. the brain.

　　C. relatives of MS patients

　　D. life expectancy

　　E. the disease

　　F. the progressive form