No.7信令的基本信令单元有哪几种？
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When the world was very young, people lived only in hot places. They did not live in cold places because they
could not keep warm there.
At first men did not know how to make a fire. Sometimes trees were hit by lightning. Then a fire was started.
People took some of the fire near their homes. A fire was very important for three reasons. It kept them warm.
Wild (野蛮的) animals were frightened when they saw it. And when food was cooked, it tasted much better.
But men did not know how to make a fire. When they had a fire, they did not let it stop burning. If it went out
(熄灭), they could not start it again. They had to wait for lightning to start another fire. Sometimes they had to
wait for years.
Later, they learned how to make a fire. But it was not easy to make something burn.
Now we have matches. We can carry them in our pockets and make a fire when we want to.
1. People found that ________. [ ]
A. the cooked food tasted better than the uncooked food
B. the uncooked food tasted much better than the cooked food
C. wild animals enjoyed the cooked food
D. wild animals kept warm near the trees
2. People didn't let a fire stop burning because ________. [ ]
A. they were not able to make a fire
B. they liked to wait for lightning
C. they were very lazy
D. they didn't like to make a fire
3. Now we can make a fire ________. [ ]
A. by lightning
B. if it is necessary
C. for three reasons
D. in our pockets
2008年5月27日，《燕赵都市报》讯：昨日上午，作为抗震救灾志愿者，在绵阳奋战了10天，年仅18岁的董常青和19岁的窦鲲鹏唐山高中学生回家了。问起两个孩子此次的收获时，两个孩子都说：“我长大了！”这意味着[ ]
A、两个孩子在年龄上已经达到了成年人的年龄了
B、参加抗震救灾，就能使人快速长大起来
C、两个孩子经历了一场血与火的严峻考验
D、两个孩子能够勇于承担社会责任，积极服务、奉献社会
BrunnstromⅣ级（）
A.手仅有极细微的屈曲
B.手无任何运动
C.手可做钩状抓握，但不能伸指
D.手可做侧捏及松开拇指
E.手可做环状和柱状抓握
下列经济业务中引起资产和负债同时减少的是( )
A．以银行存款偿还前欠单位贷款
B．以银行借款偿还应付账款
C．收到投资者投入的资本，存入银行
D．向银行借入长期借款，偿还应付账款
（）于1926年发表了两篇论著《电影导演与电影素材》和《电影剧本》。
A.维尔托夫
B.普多夫金
C.爱森斯坦
D.库里肖夫