问题 填空题

今年我国灾害性天气频现.8月12日,武汉在一天之内遭遇了高温、雷电、狂风、暴雨、冰雹,高空中的水蒸气_________(填物态变化)到小冰晶上,小冰晶变得越来越大,会从天上落下来,形成雨或雹;闪电_________(属于/不属于)光源.近来许多地方出现了严重的雾霾,如果空气中有较多的浮尘,当温度降低时,水蒸气就_________(填物态变化)成小水珠附着在这些浮尘上面,形成了雾.

答案

凝华;属于;液化

题目分析:物质由气态直接变成固态的过程叫做凝华,凝华放热.由气态变成液态的过程叫做液化,液化要放出热量.由气态的水蒸气变成固态的小冰晶属于凝华;自身能够发光的物体叫做光源,闪电自身能够发光属于光源;气态的水蒸气变成液态的小水珠属于液化.

阅读理解

     One night last February, a seventeen-year-old Duffy drove home along a winding road, he saw a

strange light thrown against the tree. "I knew it wasn't the moon", he said. "I drive this road all the time

and I notice little things out of place."

     Duffy stopped his car and got out to examine. Below him far down in the deep valley lay a broken

car with its headlights on. Thirty minutes earlier, a man had driven off the edge of the road, which has no

guardrail. His car fell and rolled end over end, landing on its top more than two hundred feet below.

     Duffy rushed to call for help, then returned and got down to reach the injured driver. Snow covered

the valley and the temperature was below freezing. After struggling back up the cliff, Duffy took off his

jacket and shirt and wrapped the injured man in time, along with the blankets from his car.

    Life-saving deeds are starting to become usual action for Duffy, the oldest of seven children. When

he was 12, he saved his ten-year-old brother from drowning. Two years ago, his three-year-old sister

ate rat poison, and Duffy cleaned out her mouth, make her drink milk to protect her stomach and called

doctors.

     "We have tried to teach the children good values, and it looks like we have got some reward for it."

His father says.

1. The strange light came from ________.

A. The bright moon.          

B. Duffy's car.

C. The broken car in the valley  

D. an unknown place

2. The phrase" landing on its top" means the car lay_________.

A. on the top of the cliff    

B. with its wheels upward  

C. with its head upward    

D. on the road as usual

3. From the above article, we can see Duffy has saved ________ at least.  

A. two    

B. three    

C. four      

D. five

4. "We have tried to teach the children good values" may probably mean Duffy's parents often tell their

children_________.

A. to help people in danger        

B. how to save people's lives

C. to remember the value of the car    

D. how to do business

单项选择题