6．是“函数的最小正周期为”的____________条件．

5.编写程序求S=1+2+3+4+…+n的和(n由键盘输入),程序如下.在如下程序的横线上应填________.　　　　　　　　　　

4．一个四边形的四个内角成等差数列，最小角为，则最大角为________.　

3．函数在=1处的导数等于_________.　　　　

2．已知向量，若与共线，则等于______.　 　　 　　　

1．设全集U = R ，A =，则=_________.

80. We are interested in the weather because it _____ us so directly ------ what we wear, what we do, and even how we feel.

　 A. benefits　　 B. guides　　 C. affects　　 D. effects

　C. affects.

　 affect (=have an influence or effect on) 影响：The climate affected his health. (气候影响[损害]了他的健康。)

[注意]affect vt. 影响。effect n. (=influent) 影响, 作用：Some films have a misleading effect on children. effect vt. (=bring about) 实行, 进行, 产生......后果:1) I will effect my purpose: no-one shall stop me! 2) We hope to effect an improvement. (我们希望能引起改进。)

注意两个常用的习语:1) to that effect 那个意思的 (话) ：She said she hated spinach, or words to that effect. (她说她不喜欢吃菠菜或那个意思的话。) 2) to the effect that... 意思时说, 表示下述意思：I said a few words the effect that all he had told us was already well known. (我说了几句话, 意思是说他告诉我们的一切都已众所周知。

79. An early typewriter produced letters quickly and neatly; the typist, _____ couldn't see his work on his machine.

　 A. however　　 B. therefore　　 C. yet　　 D. although

　A. however.　

　　 however 然而。

本题译文：早期的打字机打起字来又快又整齐, 然而打字员不能看着机器键盘打字。

78. The reason why he adapted to the new situations quickly is that he has a _____ attitude.

　 A. changeable　　 B. alternate　　 C. movable　　 D. flexible

　D. flexible.

　　 flexible 灵活的, 可变通的; We need a foreign policy that is more flexible.

77. Motorists _____ of speeding may be banned from driving for a year.

　 A. convicted　　 B. arrested　　 C. charged　　 D. judged

　A. convicted.

be convicted to 被判有...... (罪) ：He was convicted of murder. (他被法院判有谋杀罪。)