在商业银行集合境内机构和居民个人的人民币资金购汇投资境外金融产品的理财业务中，商业银

Many theories concerning the causes of juvenile delinquency (crimes committed by young people) focus either on the individual or on society as the major contributing influence. Theories (51) on the individual suggest that children engage in criminal behavior (52) they were not sufficiently penalized for previous misdeeds or that they have learned criminal behavior through (53) with others. Theories focusing on the role of society suggest that children commit crimes in response to their failure to rise above their socioeconomic status, (54) as a rejection of middle-class values. Most theories of juvenile delinquency have focused on children from disadvantaged families, ignoring the fact that children from wealthy homes also commit crimes. The latter may commit crimes (55) lack of adequate parental control. All theories, however, are tentative and are (56) to criticism. Changes in the social structure may indirectly (57) juvenile crime rates. For example, changes in the economy that lead to fewer job opportunities for youth and rising unemployment (58) make gainful employment increasingly difficult to obtain. The resulting discontent may in turn lead more youths into criminal behavior. Families have also (59) changes these years. More families consist of one-parent households or two working parents; consequently, children are likely to have less supervision at home (60) was common in the traditional family structure. This lack of parental supervision is thought to be an influence on juvenile crime rates.

58().

A. in general

B. on average

C. by contrast

D. at length

Trees ____ fight air pollution．They are natural air conditioners．

A．should

B．must

C．need

D．can

按年龄分班（）同一教育体制隔离的现象。

小鲁是一位电工，准备为一个房间设计电路，房间内两盏灯计划用并联电路，但房东邓大爷想用串联电路，他认为串联电路既简单又省钱。下面是小鲁给邓大爷的便条，请补充完整。

邓大爷： 

        您好！由于_________________________________________________，所以我设计用并联电路。

                                                                                                                                小鲁 

                                                                                                                       2009年9月17日

在质量检验中，对产品验证与产品检验的关系说法正确的是( )。

A．产品检验与产品验证互为补充

B．产品验证在前，产品检验在后

C．产品检验是产品验证的前提和基础

D．两者功能相互独立并不相关

E．产品验证是产品检验的延伸