油机是靠适时点燃吸入气缸内的柴油而爆发作功。

公元前490年到公元前322年，雅典人约有一半左右的政治家（包括伯利克里）都不同程度的受到群众惩罚，大部分控告的起因只是因为作战失利。为此，柏拉图提出了一个发人深省的问题：“如果你病了，你是召集民众为你治病呢？还是去找医术精湛的大夫呢？”材料表明： [ ]

A．伯利克里、柏拉图等人都是群众，主张实行贵族政治

B．公元前4世纪后雅典政治腐败，阶级矛盾激化

C．直接民主制可能影响民主政治的质量

D．雅典民主既体现了人民主权也保护了城邦利益

一般情况下，儿童身高在（）增加较多。

A.1-3月

B.3-5月

C.5-7月

D.9-11月

E.11月-第二年2月

黑变病表现为以面部皮肤为主的灰褐色色素沉着斑。

行使税收征收权的主体是( )。

A．地方政府

B．税务机关

C．财政部

D．国家

A conventional teacher’s licensee usually requires a university degree in education plus an unpaid term of practice teaching. This has never made much sense. It excludes bright students who take degrees in other subjects, and might teach those subjects; it is costly and time-consuming for career-switchers, who must wait a year or more before they can enter a classroom; it is so rigid that private-school teachers or university professors with years of experience have to jump through hoops before they can start teaching in a state school. And there is virtually no evidence that it creates better teachers. For all that, it is ply backed by schools of education, which have a monopoly of teacher-training, and by teachers’ unions, whose members make more money when it is artificially hard for others to get into the profession.

Now, some 45 states and the Districts of Columbia offer an "alternative route" to a teacher’s licensee, up from only a handful in the 1980s. Alternative certification (AC) generally allows individuals with a university degree to begin teaching immediately after passing an entrance examination. These recruits, watched over by a mentor teach the subject they studied at university, and take education courses at a sponsoring university while drawing their salaries.

The traditional sort of American teacher is likely to be young, white and female. Alternative certification attracts more men and more non-whites. In Texas, for instance, roughly 90% of public-school teachers are white, but 40% of those who have joined through alternative certification are non-whites. The AC route also draws teachers willing to go where they are most needed. A survey of Troops to Teachers, a program that turns exsoldiers into public-school teachers (" Proud to serve again"), found that 39% of those taking part are willing to teach in inner-city schools, and 68% in rural areas.

Are they good teachers Officialdom is reluctant to release the details which might answer that question for certain. But anecdotal evidence suggests they do well. In New Jersey, which has been running this sort of program since 1984, rich districts, which can afford to be choosy, consistently hire more AC teachers than poor districts do. In Houston, Texas, where the Teach of America program (TFA) puts recent university graduates into poor communities as teachers, the most effective teachers are generally the TFA ones. " School principals are our biggest fans," Wendy Kopp, TFA’s president, says proudly.

So why not scrap the cumbersome teacher-licensing laws Frederick Hess, a professor at the University of Virginia, has written a paper for the Progressive Policy Institute arguing that teacher-licensing ought to be stripped to the bare essentials. Prospective teachers should be required only to hold a college degree, pass a test of essential skills, and be checked to make sure they do not have a criminal background. Other training is important, argues Mr. Hess, but the market, not state legislators, should decide what that training looks like. This notion of "competitive certification" has drawn favorable attention from the Bush administration.

How does the author feel about the conventional teacher’s training（）

A. Ridiculous

B. Unjust

C. Complicated

D. Irrelevant