閱讀下面短文，掌握其大意，然后從41—50各題所給的四個選項中選出一個最佳答案。

　　Water is the most important of all the things we eat and 41. Not many people understand this, but it's quite 42. The human body( A￡)can go without 43 for a long time, yet two or three days 44 water can usually make people die.

　　Many people don't understand how 45 water the human body needs 46 work well, and many people do not drink enough, 47 in hot weather. Our body is mostly(:大部分)water about 67-75 percent(百分之). 48 we don't have enough, we'll feel 49 and many will get ill. So, you 50 , how important water is to us all.

　　41. A. have B. drink C. take D. cook

　　42. A. true B. difficult C. easy D. wrong

　　43. A. food B. water C. drink D. air

　　44. A. in B. through C. without D. with

　　45. A. many B. much C. widely D. a bit

　　46. A. and B. to C. its D. or

　　47. A. even B. ever C. almost D. still

　　48. A. Because B. For C. Since D. If

　　49. A. worried B. angry C. tired D. afraid

　　50. A. hear B. know C. guess D. look