21. Just as Martin Luther King, Jr. said, peace is not merely a distant goal that we seek, but a means ________ we arrive at that goal.

38. I have no alternative ______ to arrive late.

23. —The government must have taken measures to lower the house prices next year, ________ it?— Yes. I guess so.

47. Over the past two decades, the popularity of the bicycle as a mean of transportation and recreation has increased tremendously in the United States.

7. The police have already investigated some witnesses and the ________ is that it was just an accident, even among the families.

10.（ ）是教育心理学研究中所采用的最普遍、最基本的方法。

22. When a child is ________ to peanuts, families must closely monitor everything the child eats both in and outside the home, because accidental consumption of peanuts could cause death.

55. To stay warm in cold weather, cold-blooded animals must expose itself to a source of warmth such as direct sunlight.

7.根据我国《义务教育法》的规定，凡年满六周岁的儿童，其父母或者其他法定监护人应当送其入学接受并完成义务教育：条件不具备的地区的儿童，可以推迟到十周岁。（ ）

37. The car gathered speed and soon ______ view.

2.以下属于班级管理原则的是（ ）。

5. Great changes _____ in my home town and a lot of factories _____.