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Teachers need to be aware of the emotional, intellectual, and physical changes that young adults experience. And they also need to give serious (21) to how they can be best (22) such changes. Growing bodies need movement and (23) , but not just in ways that emphasize competition. (24) they are adjusting to their new bodies and a whole host of new intellectual and emotional challenges, teenagers are especially self-conscious and need the (25) that comes from achieving success and knowing that their accomplishments are (26) by others. However, the typical teenage lifestyle is already filled with so much com petition that it would be (27) to plan activities in which there are more winners than los ers, (28) , publishing newsletters with many student-written book reviews, (29) student artwork, and sponsoring book discussion clubs. A variety of small clubs can pro vide (30) opportunities for leadership, as well as for practice in successful (31) dynam ics. Making friends is extremely important to teenagers, and many shy students need the (32) of some kind of organization with a supportive adult (33) visible in the back ground.In these activities, it is important to remember that the young teens have (34) at tention spans. A variety of activities should be organized (35) participants can remain ac tive as long as they want and then go on to something else without feeling guilty and with out letting the other participants down. 26（）
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关系模式规范化需要考虑数据间的依赖关系，人们已经提出了多种类型的数据依赖，其中最重要的是函数依赖和 【9】 。
下面______是回送地址。
M: That was a really interesting movie. I hope you enjoyed it, too.W: But I fell asleep just after it started. How did the woman feel about the movie（）
Much of the research on hallucinogenic drugs such as LSD has focused on the neurotransmitter serotonin, a chemical that when released from a presynaptic serotonin-secreting neuron causes the transmission of a nerve impulse across a synapse to an adjacent postsynaptic, or target, neuron. There are two major reasons for this emphasis. First, it was discovered early on that many of the major hallucinogens have a molecular structure similar to that of serotonin. In addition, animal studies of brain neurochemistry following administration of hallucinogens invariably reported changes in serotonin levels.Early investigators correctly reasoned that the structural similarity to the serotonin molecule might imply that LSD’ s effects arc brought about by an action on the neurotransmission of serotonin in the brain. Unfortunately, the level of technical expertise in the field of brain research was such that this hypothesis had to be tested or, peripheral tissue ( tissue outside the brain). Two different groups of scientists reported than LSD powerfully blockaded serotonin’ s action, their conclusions were quickly challenged, however. We now know that the action of a drug at one site in the body does not necessarily correspond to the drug’ s action at another site, especially when one site is in the brain and the other is not.By the 1960’ s technical advances permitted the direct testing of the hypothesis that LSD and related hallucinogens act by directly suppressing the activity of serotonin secreting neurons themselves—the so called presynaptic hypothesis. Researchers reasoned that if the hallucinogenic drags act by suppressing the activity of serotonin-secreting neurons, then drugs administered after these neurons had been destroyed should have no effect on behavior, because the system would already be maximally suppressed. Contrary to their expectations, neuron destruction enhanced the effect of LSD and related hallucinogens on behavior. Thus hallucinogenic drugs apparently do not act directly on serotonin-secreting neurons.However, these and other available data do support an alternative hypothesis, that LSD and related drugs act directly at receptor sites on serotonin target neurons (the postsynaptic hypothesis). The fact that LSD elicits "serotonin syndrome", that is, causes the same kinds of behaviors as does the administration of serotonin in animals whose brains are depleted of serotonin indicates that LSD acts directly on serotonin receptors, rather than indirectly through the release of stores of serotonin. The enhanced effect of LSD reported after serotonin depletion could be due to a proliferation of serotonin receptor sites on serotonin target neurons. This phenomenon often follows neuron destruction or neurotransmitter depletion; the increase in the number of receptor sites appears to be a compensatory response to decreased input. Significantly, this hypothesis is supported by number of different laboratories, The research described in the passage is primarily concerned with answering which of the following questions（）
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