WE MUSTN'T F___ THE HISTORY

We mustn't talk loudly in the library must是情态动词, 情态动词后面只能跟动词原形

play,情态动词后加动词原形

第一句中的must 是表示肯定语气,可以翻译成一定,肯定.第二句中的mustn't 是表示不准,不能,不可以的禁止语气.因为两个句子中must的意思各不相同,所以反义疑问句就不同.再举例：He must have stolen people's money, didn't he? 指他过去肯定偷过钱. You mustn't leave the room, will you?

World University Games,known as "Little Olympics," said,by "organized by the International University Sports Federation,only college students and graduates of not more than two years of college students (age limit is 17-28 years old) to participate in the world of large-scale integrated Games.was initiated in 1959,its predecessor,the International University Games.As of March 2009,the World University Games have been held 25 sessions.
In 1960,the imitation of the Olympic Games competition system,and Chamonix in France,organized the World University Winter Games.Initially,the Summer Games and Winter Games are in odd-numbered years and held since 1981 to be held in the same year.To 1999,the World University Winter Games have been held 19 sessions,events have speed skating,short track speed skating,figure skating,alpine skiing,cross country skiing,ski jumping,biathlon,ice hockey,Nordic,snowboarding.
世界大学生运动会,素有“小奥运会”之称,由“国际大学生体育联合会主办,只限在校大学生和毕业不超过两年的大学生（年龄限制为17-28岁）参加的世界大型综合性运动会.始办于1959年,其前身为国际大学生运动会.截止至2009年3月,世界大学生运动会已举办过25届.
1960年,仿奥运会赛制,又在法国夏蒙尼举办了世界大学生冬季运动会.起初,夏季运动会和冬季运动会分别在单数和双数年举行,从1981年起改为在同一年举行.至1999年,世界大学生冬季运动会已举办过19届,比赛项目有速度滑冰、短道速滑、花样滑冰、高山滑雪、越野滑雪、跳台滑雪、冬季两项、冰球、北欧两项、滑板滑雪.

选 A leave 落下
我们不能把不干净的餐具落在厨房里.

我们决不能随意破坏学校里的花草树木
We must not destroy the trees and flowers in the school
我们决不能上课不专心We must not inattentive in class
我们决不能上课讲话We must not talk in class

pollute