【单选题】Advertisements are only read by a small group of people of high social status.
【单选题】Sociologists have long recognized that social tensions are______elements of group life.
【简答题】Advertisements are only read by a small group of people of high social status.
【简答题】请写出硝化过程和反硝化过程的反应式,并比较硝化作用和反硝化作用的异同。
【判断题】In social relationships that stress group values, people usually seek suggestions from their friends, family members and colleagues.()