医患关系的性质是（）。 A.医患关系是一般的契约关系 B.医患关系是纯粹的信托关系

全冠修复后引起牙龈炎症的原因中不包括（）

A.食物嵌塞

B.复体边缘不密合

C.修复体轴面外形不正确

D.咬合不平衡

E.光洁度差，边缘粗糙

I thought l was going to fail the driving test but I succeed       ．[ ]

A.   after all        

B.   first of all    

C．in all        

D．at all

硅整流发电机转子爪极间组成（ ）磁极。

A.2对

B.4对

C.6对

D.8对

In the absence of optimism, we are left with nothing but critics, naysayers, and prophets of doom. When a nation expects the worst from its people and institutions, and its experts focus exclusively on faults, hope dies. Too many people spend too much tie looking down rather than up, finding fault with their country’s political institutions, economic system, educational establishment, religious organizations, and—worst of all—with each other.

Faultfinding expends so much negative energy that nothing is left over for positive action. It takes courage and strength to solve the genuine problems that afflict every society. Sure, there well always be things that need fixing. But the question is, do you want to spend your time and energy tearing things down or building them up

The staging of a Broadway show could illustrate my point. Let’s say a new production is about to open. A playwright has polished the script, investor have put up the money, and the theater has been rented. A director has been chosen, actors have been auditioned and selected, and the cast has been rehearsing for weeks. Set, lighting, and sound engineers have been hard at work. By the time opening night arrives, nearly a hundred people have labored tirelessly—all working long hours to make magic for their audience.

On opening night, four or five critics sit in the audience. If they pan it, the play will probably close in a matter of days or weeks. If they praise it, the production could go on for a long and successful run. In the end, success or failure might hinge on the opinion of a single person—someone who might be in a bad mood on opening night! What’s wrong with this scene In one sense, nothing. Critics have a legitimate role. The problem arises when we make critics our heroes or put them in control of our fate. When we empower the critic more than the playwright, something is wrong. It is much easier to criticize than to create. When we revere the critics of society, we eventually become a society of critics, and when that happens, there is no room left for constructive optimism.

The preparation of a Broadway show is mentioned in order to ().

A. explain that staging a play requires complex teamwork

B. argue that a minute mistake may ruin a lifelong task

C. show that the preparatory stage is imperative the following ones

D. illustrate that criticism may block the way to success

汽轮机保安系统由（）等几部分组成。

A、危急遮断器及危急遮断油门

B、磁力断路油门

C、轴向位移保护装置

D、低油压保护装置