【单选题】【消耗次数：1】
哨子在使用中的注意事项不包括（ ）。
①
注意频率适度
②
注意使用方法
③
注意保持距离
④
注意轻重有度
参考答案：
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相关题目
【单选题】
使用排龈线的注意事项不包括（）
①
操作轻柔
②
肾上腺素不容易氧化，无需密封保存
③
放入排龈线前，冲洗干净龈沟内的唾液和血液
④
5分钟左右取出排龈线，立即制取印模
⑤
以上均正确
【多选题】
使用手势的注意事项有（）
①
注意区域性差异
②
手势不宜过多，动作幅度不宜过大
③
注意手势速度和高度
④
手势一定要自然、协调
⑤
用手示意别用指头指
⑥
手势指人要注意，不要掌心向下
【单选题】
氧头孢烯类抗菌药物使用注意事项不包括（ ）
随机题目
【单选题】
A new house ___ at the corner of the road.
①
is building
②
is being built
③
been built
④
be building
【单选题】
阅读理解：阅读下列短文，回答文后问题，选择最佳答案Trees mainly serve man in three important ways: They provide him with wood and other products; they provide him shade; and they help to prevent droughts and floods.Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important．In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And besides, he is usually too careless to plant and look after new trees. So the forests slowly disappear.This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil allowing the rain to sink in and also bind(固定) the soil, thus preventing it from being washed away easily；but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When the top-soil is gone, nothing remains but worthless desert.Two thousand years ago，a rich and powerful country cut down its trees to build warships, with which to gain itself an empire．It set up the empire, but, without its trees, its soil became poor and grew weak. When the empire fell to pieces, the home country found itself faced by floods and starvation(饥荒)．4. Why did the country mentioned in the passage suffer from floods and starvations?
①
A. Because it set up an empire.
②
B. Because it fell to pieces.
③
C. Because it turned its trees into warships.
④
D. Because it spent too much money on wars.
【单选题】
阅读理解：阅读下列短文，回答文后问题，选择最佳答案Trees mainly serve man in three important ways: They provide him with wood and other products; they provide him shade; and they help to prevent droughts and floods.Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important．In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And besides, he is usually too careless to plant and look after new trees. So the forests slowly disappear.This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil allowing the rain to sink in and also bind(固定) the soil, thus preventing it from being washed away easily；but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When the top-soil is gone, nothing remains but worthless desert.Two thousand years ago，a rich and powerful country cut down its trees to build warships, with which to gain itself an empire．It set up the empire, but, without its trees, its soil became poor and grew weak. When the empire fell to pieces, the home country found itself faced by floods and starvation(饥荒)．3. Land becomes desert after all trees are cut down because __________.
①
A. roots of trees break up the soil
②
B. no tree keeps the rain and protects the top-soil
③
C. strong winds bring a lot of sand
④
D. there are too many rainfalls to make it
【单选题】
阅读理解：阅读下列短文，回答文后问题，选择最佳答案Trees mainly serve man in three important ways: They provide him with wood and other products; they provide him shade; and they help to prevent droughts and floods.Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important．In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And besides, he is usually too careless to plant and look after new trees. So the forests slowly disappear.This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil allowing the rain to sink in and also bind(固定) the soil, thus preventing it from being washed away easily；but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When the top-soil is gone, nothing remains but worthless desert.Two thousand years ago，a rich and powerful country cut down its trees to build warships, with which to gain itself an empire．It set up the empire, but, without its trees, its soil became poor and grew weak. When the empire fell to pieces, the home country found itself faced by floods and starvation(饥荒)．1. According to the passage, which is the most important service of trees to man?
①
A. They help him make money.
②
B. They give him cool.
③
C. They give him wood and other things.
④
D. They help him to stop droughts and floods.
【单选题】
These papers___yet.
①
have not written
②
have not been written
③
has not written
④
has not been written