If someone asked you, What color is the sky? I expect that you would answer, Blue. I am afraid that you would be wrong. The sky has no color. When we see blue, we are looking at blue sunlight. The sunlight is shining on little bits of dust in the air.
What is the sky? The sky is space. In this space there is nothing except the sun, the moon and all the stars.
The moon is about 384,000 kilometers away from the earth. An airplane cannot fly to the that can fly even when there is no air. This is rocket.
This is how a rocket works. It is not made of rubber like a balloon, of course. It is made of metal. The metal must not be heavy but it must be very strong. There is gas inside the rocket which is made very hot. When it rushes out of the end of the rocket, the rocket is pushed up into the air.
练习:
A) It is blue.
C) It is grey.
2. When an airplane flies too high,
B) the air will become thicker.
D) the air will disappear in no time.
A) it looks like a balloon.
C) it doesnt have wings.
4. Which of the following statements about a rocket is NOT true?
B) It can fly without wings.
D) It is propelled by burning gas inside it.
A) hot gas rushes out of its head.
C) hot gas rushes out of its bottom.
Keys:DADDC
人教新版英语六下《Unit 3》PPT课件5
人教版新起点英语一上《Unit 2》PPT课件
人教新版英语六下《Unit 1 (Revision)课件包(含声音素材)》PPT课件包
2013人教版(新起点)一上《Unit 4 revision》ppt课件1
2013人教版(新起点)一上《Unit 1 School》ppt课件
2013人教版(新起点)一上《Unit 6 Colours》ppt课件
人教新版英语六下《Unit 3 Lesson 15》PPT课件1
人教版新起点英语一上《Unit 4 Revision》PPT课件
2013人教版(新起点)一上《Unit 5 Numbers》ppt课件
2013人教版(新起点)一上《Unit 6 Colours》ppt课件1
2013人教版(新起点)一上《Unit 8 Revision》ppt课件1
2013人教版(新起点)一上《Unit 6 Colours》ppt课件3
2013人教版(新起点)一上《Unit 7 Fruit》ppt课件
人教新版英语六下《Unit 2 lesson11-12》PPT课件
人教新版英语六下《Unit 2 Part B let‘s learn》PPT课件
人教版新起点英语一上《Unit 1 School》PPT课件2
人教新版英语六下《We are going to visit the Great Wall》PPT课件
人教新版英语六下《Unit 3》PPT课件3
2013人教版(新起点)一上《Unit 8 Revision》ppt课件
2013人教版(新起点)一上《Unit 5 Numbers》ppt课件2