The moving stones
These big stones leave long tracks behind them. The long tracks show that the stones have moved along the ground. But how do they move? Scientists have tried to answer this question for the last 50 years.
These famous moving stones are in Death Valley. USA. Many of the stones are small but a few of them are very big. Some of the big stones are as big as a man. The biggest stones weigh 350 kilograms. They are heavier than four men!
The stones only move at night and only once every year or two. Nobody has ever seen them moving, out now scientists know the answer to the question.
The answer is the wind. When the wind comes from the west, the stones move to the east. When the wind is from the south, they always move to the north. But how can the wind move a stone that weighs 350 kilograms?
This answer is more complicated. Death Valley is one of the hottest places in the world, but it can be very cold at night. Sometimes there are bad storms in the night. Rain falls, and the hard ground becomes soft and wet. The wind is very strong and cold. The water on the ground changes to very thin ice. Then the strong wind can move flat stones along the flat ground. In the morning the sun comes up and dries the ground
Read the text
1. Choose the correct letter – a, b, c
1of the moving stones are very heavy.
a) All b) Some c) None
2. They move the same way as the wind.
a) always b) sometimes c) never
3. The ……… longer and more difficult
a) second answer is b) first question is c) bigger stones are
4. The nights are…...
a) never stormy b) hot in the day time c) sometimes very cold and wet
5. The wind can move stones because the ground is
a) soft and wet b) flat and icy c) hot and dry
2/ Say if it is TRUE or FALSE
6. These small stones leave long tracks behind them
7. These famous moving stones are in Death Valley, USA.
8. These stones move only at night and only twice every year or two.
9. Death Valley is one of the hottest places in the world.
10. There can be very cold at night.
3/ Retell the text
1)
1. b) Some
2. c) Never
3. a) second answer is
4. c) sometimes very cold and wet
5. b) flat and icy
2)
6. False
7. True
8. True
9. True
10. True