.讨论--练习阅读真功夫

himba

请哪阅读高人指点:

都说练习阅读要从找主题句做起,现在发现这点也不是很容易,有时找不到主题句,或不知哪句是. 有时把主题句划得太多又失去了意义.如果如下问题很可笑,请别见怪,可是这确实一直困扰我


1)请问下面一段的主题句,主题句只有一句吗?主题句应该是其事实总结呢,还是评价呢?还是全部呢?那位dx根据做题经验讲解一下?
For many years, caffeine’s effects have been attri-
(20) buted to its inhibition of the production of phosphodi-
esterase, an enzyme that breaks down the chemical
called cyclic AMP.A number of neurotransmitters exert
their effects by first increasing cyclic AMP concentra-
tions in target neurons. Therefore, prolonged periods at
(25) the elevated concentrations, as might be brought about
by a phosphodiesterase inhibitor, could lead to a greater
amount of neuron firing and, consequently, to behav-
ioral stimulation. But Snyder et al point out that the
caffeine concentrations needed to inhibit the production
(30) of phosphodiesterase in the brain are much higher than
those that produce stimulation. Moreover, other com-
pounds that block phosphodiesterase’s activity are not
stimulants.

2)下面一段的主题句又是哪一句呢?主题句的特点应是什么呢?

You might object that professionals excavate to
acquire knowledge, not money. Moreover, ancient arti-
facts are part of our global cultural heritage, which
should be available for all to appreciate, not sold to the
highest bidder. I agree. Sell nothing that has unique
(25) artistic merit or scientific value. But, you might reply,
everything that comes our of the ground has scientific
value. Here we part company. Theoretically, you may be
correct in claiming that every artifact has potential scien-
tific value. Practically, you are wrong.

谢谢![em08]

robert

这样段落的中心句又该怎样归纳?

MESBIC’s are the result of the belief that providing
established firms with easier access to relevant manage-
ment techniques and more job-specific experience, as
(30) well as substantial amounts of capital, gives those firms
a greater opportunity to develop sound business founda-
tions than does simply making general management
experience and small amounts of capital available.
Further, since potential markets for the minority busi-
(35) nesses already exist through the sponsoring companies,
the minority businesses face considerably less risk in
terms of location and market fluctuation. Following
early financial and operating problems, sponsoring
corporations began to capitalize MESBIC’s far above
(40) the legal minimum of $500,000 in order to generate
sufficient income and to sustain the quality of manage-
ment needed. MESBIC’c are now emerging as increas-
ingly important financing sources for minority enter-
prises.fficeffice" />

hsWang

可以平常放慢速度，仔细寻找。然后加快速度


看多了练多了，自然就能快速定位主体句了