一个由20种、500个氨基酸组成的蛋白质，它的氨基酸的排列顺序可能是 [ ] A

下列各句中，没有语病的一项是

A．世界近代史证明，如果一个民族完全遗忘了自己的过去，那么必将失去自己的独立性而沦为别的民族的附庸，将受别的民族的奴役。

B．曼德拉出生于特兰斯凯一个大酋长家庭，但南非实行的种族隔离制度却让曼德拉从小就感受到了种种歧视和不公平。

C．这次环保大会，吸引了来自一百多个国家与地区的专业人士参加这次近年来规模最大、议程最多的会议，并取得了预期的效果。

D．经济发展必须优先解决损害群众健康的问题，否则，若不坚持科学发展，让健康人变成了病人，这种发展便是具有讽刺意味的，是不健全的。

阅读下面的材料，根据要求写一篇不少于800字的文章。

2014年是农历甲午马年，快马加鞭是常说的话语。

楠木，木质坚硬，木材名贵，生长缓慢，成为栋梁材要上百年。

上世纪民国时期去趟欧洲，坐轮船得花一个月的时间。在途中可以阅读，写家书，思乡……，精神生活丰富多彩。

高铁，速度至少达到250公里／小时，为人们的出行带来便捷。可是，一些发达国家的老百姓拒绝高铁，也没见得人家的日子过得有多难受。

要求：①选准角度，自定点意：②自拟题目；③除诗歌外，文体不限，文体特征鲜明；④不要脱离材料内容及含意的范围。

患者，男，35岁。再生障碍性贫血3年。面色无华，头晕，气短，乏力；动则加剧，舌淡，苔薄白，脉细弱。治疗应首先考虑的方剂是

A．右归丸合当归补血汤
B．左归丸、右归丸合当归补血汤
C．八珍汤
D．六味地黄丸合桃红四物汤
E．左归丸合当归补血汤

按功能区分，库存的基本类型有（）

A.波动库存

B.预期库存

C.批量库存

D.运输库存

E.屏障库存

"Sesame Street" has been called "the longest street in the world". That is because the television program by that name can now be seen in: so many parts of the world. That program became one of American’s exports soon after it went on the air in New York in 1969.
In the United States more than six million children watch the program regularly. The viewers include more than half the nation’s preschool children, from every kind of economic, racial, and geographical group.

Children who often watch the program ______ .
A. can have problems in school
B. will find it a great help
C. will take no interest in their studies
D. will be well educated

Although some educators object to certain elements in the program, parents praise it highly. Many teachers also consider it a great help, though some teachers find that problems arise when first graders who have learned from "Sesame Street" are in the same class with children who have not watched the program.
Tests have shown that children from all racial, geographical, and economic backgrounds have benefited from watching it. Those who watch it five times a week learn more than occasional viewers. In the US the program is shown at different hours during the week in order to increase the number of children who can watch it regularly.
The programs all use songs, stories, jokes, and pictures to give children a basic understanding of numbers, letters and human relationships. But there are some differences. For example, the Spanish program, produced in Mexico City, devotes more time to teaching whole words than to teaching separate letters.
Why has "Sesame Street" been so much more successful than other children’s shows Many reasons have been suggested. People mention the educational theories of its creators, the support by the government and private businesses, and the skillful use of a variety of TV tricks. Perhaps an equally important reason is that mothers watch it along with their children. This is partly because famous adult stars often appear on it. But the best reason for: the success of the program may be that it makes every child watching feel able to learn. The child finds himself learning, and he wants to learn more.