Ⅲ. Read and choose.（阅读材料，选择正确答案。）
Dear Emma,
How are you? I just got back from school with good news. Tomorrow we are going to have the third live(现场直播的) class of the “Tiangong Class” series.
The last two live classes were very amazing. The teachers were taikonauts working in China's space station Tiangong. I got to know a lot about science in space. The taikonauts can't walk in the space station. They “fly”. Water becomes magic in space. In the first live class of the “Tiangong Class” series, the ping-pong ball didn't float(漂浮) on the water surface(表面) as it does on Earth. It stayed inside the water. Why is that? Buoyancy(浮力) arises(产生) due to gravity(重力). But in space, there is almost（几乎） no gravity. So there is almost no buoyancy. The ping-pong ball cannot float up. It is different from that on Earth.
I will tell you about the third live class of the “Tiangong Class” series next time.
Yours,
Taotao
（）1. Where were the teachers of the “Tiangong Class” series?
A. In Taotao's school. B. In the science museum.
C. In the space station.
（）2. What can we know about buoyancy and gravity?
A. There is no buoyancy on Earth.
B. Buoyancy arises due to gravity.
C. There is no gravity in space.
（）3. Where will the ping-pong ball go if you put it in the water in space?

A. B. C.
（）4. What is Taotao's letter mainly(主要地) about?
A. Emma's school. B. The “Tiangong Class” series.
C. China's space station.

1. C 2. B 3. A 4. B

【分析】
本题为英语阅读理解题，需结合原文内容逐一分析每个问题：第1题定位天宫课堂老师的位置，第2题考查浮力与重力的关系，第3题结合太空无浮力的知识判断乒乓球的状态，第4题概括信件主旨，均需从原文提取关键信息作答。
【解析】
1. 细节理解题：根据原文第二段“The teachers were taikonauts working in China's space station Tiangong.”可知，天宫课堂的老师在空间站，故选C。
2. 细节理解题：原文明确提到“Buoyancy arises due to gravity.”，即浮力由重力产生，故选B。
3. 细节理解题：原文指出太空几乎无浮力，乒乓球不会漂浮，对应插图A（球在水中），故选A。
4. 主旨大意题：信件围绕“天宫课堂”系列课程展开，介绍了前两次课程的内容及第三次课程的预告，故选B。
【答案】
1.C 2.B 3.A 4.B
【知识点】
英语阅读理解、细节理解、主旨大意
【点评】
本题结合热点科普内容，考查学生提取细节信息和概括主旨的能力，题目设置贴近原文，难度适中，适合学生巩固阅读理解的基本解题方法。
【难度系数】
0.6