题目

阅读资料，回答问题。将装有两种不同气体的两个容器连通，经过一段时间，两种气体就在这两个容器中混合均匀，这种现象叫做扩散。在液体间和固体间也会发生扩散现象。例如清水中滴入几滴红墨水，过一段时间，水就都染上红色；又如把两块不同的金属紧压在一起，经过较长时间后，每块金属的接触面内部都可发现另一种金属的成分。 （1） 从扩散现象可以看出，固体分子间距离较，作用力较，大多数分子只能在一定的位置振动，不能移With the introduction of family planning policies in the 1970s, most Chinese teenagers have no brothers or sisters．They get to be the beloved（心爱的）__21__child．But they may not realize that they will have to “__22__” the love as their__23__ones grow old．They will have to__24__lots of old people—their parents, grandparents, their_  25  _parents and grandparents． China is becoming__26_  country． According to the United Nations, an aging society refers to one    27   10 percent or more of the population is over 60, or 7 percent or more is over 65. According to   28   from the Ministry of Civil Affairs, by 2008, Chinese over 60 years old made up 12 percent of the nation’s total population. The    29    for those aged 65 or older was 8.3 percent. In China, people have a belief that “parents raise children; then the children care for the parents as they get old”．But this__30__is under stress as the market economy puts millions of young Chinese on the road__31__better paying jobs．They are leaving their parents__32_．Now many families are looking more to the government than to their__33__for support when they’re old．China has increased its basic social security（基本社会保险）plan which is__34__protecting those__35__, including the old, the disabled and others．These programs are now broad, __36_they are still not highly developed． As more people grow__37__, China will have fewer working people, __38__will slow down economic growth．According to a November 26 report in the Economic Information Daily, an expert said China should __39__its people to have more than one child in the future__40_China should keep its labor population and total population size stable（稳定的）． 21．A．only B．lonely C．friendly D．heartily 22．A．take up B．take back C．pay back D．pay for 23．A．hated B．loved C．tired D．hearted 24．A．care for B．bring up C．look for D．pay attention to 25．A．daughter’s or son’s B．niece’s or nephew’s C．wife’s or husband’s D．aunt’s or uncle’s 26．A．an old B．an aging C．a developing D．a developed 27．A．where B．when C．which D．that 28．A．an article B．an email C．a magazine D．a report 29．A．conclusion B．character C．figure D．survey 30．A．tradition B．opinion C．saying D．way 31．A．in favor of B．in search of C．in the way of D．in the face of 32．A．out B．off C．ahead D．behind 33．A．friends B．relatives C．parents D．children 34．A．an act B．a case C．a program D．a plan 35．A．in danger B．in need C．in desperate D．in disaster 36．A．but B．or C．and D．so 37．A．strong B．realistic  C．rich D．old 38．A．as B．which C．what D．that 39．A．forbid B．promise C．encourage D．order 40．A．so that B．though C．even if D．because