An annoying problem for humans, who like to boast (夸耀) about all the distant planets and moons we have explored, is that we've never taken a good look right under our noses. The inside of the earth is relatively close, but how can we get there?

The deepest oil well enters a mere six miles into the crust (地壳) (the center of the earth is about 4,000 miles deeper). Russian scientists dug the deepest hole in Siberia, but bottomed out at about 7.5 miles below the surface. The Mohole project, a U.S. plan in the 1950s, called for drilling a hole 25 miles down to the boundary between the hard rocks of the crust and the soft mantle (地幔). Sadly the project involved government supporting.

It gets harder and harder to drill deep into the earth because rocks get softer and softer. Hard but easily broken at the surface, rocks become plastic at depth, and the pressure caused by the weight of the overlaying crust ---  about 52,800 pounds per square inch at a depth of ten miles, makes further drilling impossible.

What little we know about the inside of the earth (like the fact that there's a crust, a mantle, and a core) comes from indirect evidence, such as the analysis of earthquakes.

So maybe it's time for a thorough new method to explore the earth's inside. Scientist David Stevenson says we should forget about drilling holes. Instead, we should open a crack (裂缝).

Stevenson suggests digging a crack about a half mile long, a yard wide, and a half mile deep (not with a shovel) but with an explosion on the scale of a nuclear bomb. Next, he'd pour a few hundred thousand tons of molten (熔化的) iron into the crack, along with a robot. The iron, thicker than the surrounding crust, would move downward at about 16 feet per second, carrying the robot with it and opening the crack deeper and deeper. The iron mass would drop for about a week and 2,000 miles to the outer edge of the earth core, the robot sending out data to the surface.

Stevenson compares his idea to space exploration. "We're going somewhere we haven't been before,"he says. "In all possibility, there will be surprises.”

This idea can probably be put in the drawer marked with Isn't Going To Happen. The robot would have to survive temperatures that would melt pretty much anything. But Stevenson's idea may inspire a new look at an old problem. Great things can come from what seems like impossible ideas.

Going inside the earth is _____ than going into space.

A. more interesting B. more possible C. easier  D. more challenging

How deep have we gone into the earth until now?

A. 6 miles.  B. 4,000 miles. C. 7.5 miles.  D. 25 miles.

Which of the following is TRUE about David Stevenson's idea?

A. It is an inspiring but not practical idea now.

B. It is a practical proposal that has come into use now.

C. It is a good proposal that will soon be put into practice.

D. It is a false theory that cannot be carried out at all.

What might be the most suitable title for the text?

A. An Annoying Problem for Humans

B. To the Center of the Earth

C. The Mohole Project

D. David Stevenson's Proposal

It is easier to float in the ocean than it is to float in a swimming pool. Do you know why?
Ocean water is full of salt— and salt water can hold up more weigh than fresh water. See for yourself!
You Will Need:
● 3 cups of warm water
● Measuring cup (量杯)
● Wide-mouthed jar
● Salt
● Spoon
● Raw (生的)potato
You Will Do:
1. Pour 1.5 cups of warm water into the jar.
2. Add 1/3 cup of salt.
3. Stir(搅拌) until the salt is completely dissolved.
4. Add another 1.5 cups of water. Pour it slowly over the back of the spoon into the jar so that the two liquid will not mix together.
5. Gently place the potato into the jar. Do not drop it.
What Will Happen:
The potato will sink— but only halfway!
Why?
Salt water is heavier than fresh water, so it will stay on the bottom. The fresh water will remain on top.
The potato is heavier than the fresh water, but it is lighter than the salt water. That is why the potato will sink halfway down.
【小题1】In the experiment, what should you do right after you pour the water over the spoon?

A．Add the salt to the water.	B．Stir the salt into the water.
C．Place the potato in the jar.	D．Pour warm water into thejar.

【小题2】In Step 4 of the experiment, why do you pour the water over the spoon “slowly”?

A．It is easier to see what you are doing.

B．It pushes the fresh water to the bottom.

C．It will keep the water from coming out.

D．It will keep the liquids from mixing together.

【小题3】In which step of the experiment do you add the salt?

A．Step 1

B．Step 2

C．Step 3

D．Step 4

【小题4】What does the underlined word “gently” mean?

A．Carefully

B．Quickly

C．Secretly

D．Silently

阅读下面短文，根据以下要求：1）汉语提示, 2）首字母提示, 3）语境提示, 在每个空格内填入一个适当的英语单词，并将该词完整地写在右边相对应的横线上，所填单词要求意义准确，拼写正确。

Hello, everyone. My name is water. I’m one of the most important     1.    (自然) resources in the world. I’m very       proud of     2.      because almost no everyday tasks can beperformed w   3.      me. My nickname is liquid gold because I’m precious. People in some areas are always _____4.___(埋怨) about not having enough of me. W   5.      still, only 5 per cent of the fresh water is _______6.____(可用的) in rivers and lakes. So protect me and save as    7.     of me as possible!. Remember: don’t leave the tap r   8.    when you brush your teeth. Don’t throw rubbish into rivers,      9.    . Nor pour me into them when I’m dirty.Never waste even a drop, o   10.    you’ll run out of me in the near future. 

 

An annoying problem for humans, who like to boast (夸耀) about all the distant planets and moons we have explored, is that we've never taken a good look right under our noses．The inside of the earth is relatively close but how can we get there?

The deepest oil well enters a mere six miles into the crust (地壳)  (the center of the earth is about 4,000 miles deeper)．Russian scientists dug the deepest hole in Siberia," but bottomed out at about 7.5 miles below the surface．The Mohole project, a U.S．plan in the 1950s, called for drilling a hole 25 miles down to the boundary be??tween the hard rocks of the crust and the soft mantle (地幔)．Sadly the project involved govern??ment supporting.

It gets harder and harder to drill deep into the earth because rocks get softer and softer． Hard but easily broken at the surface, rocks become plastic at depth, and the pressure caused by the weight of the overlaying crust — about 52,800 pounds per square inch at a depth of ten miles, makes further drilling impossible.

What little we know about the inside of the earth (like the fact that there' s a crust, a mantle, and a core) comes from indirect evidence, such as the analysis of earthquakes.

So maybe it' s time for a thorough new method to explore the earth's inside．Scientist David Stevenson says we should forget about drilling holes．Instead, we should open a crack (裂缝)． 

Stevenson suggests digging a crack about a half mile long, a yard wide, and a half mile deep (not with a shovel) but with an explosion on the scale of a nuclear bomb．Next, he'd pour a few hundred thousand tons of molten (融化的) iron into the crack, along with a robot．The iron, thicker than the surrounding crust, would move downward at about 16 feet per second, carrying the robot with it and opening the crack deeper and deeper．The iron mass would drop for about a week and 2,000 miles to the outer edge of the earth core, the robot sending out data to the sur??face.

Stevenson compares his idea to space explo??ration．"We're going somewhere we haven't been before," he says．"In all possibility, there will be surprises."

This idea can probably be put in．the drawer marked with Isn't Going To Happen．The robot would have to survive temperatures that would melt pretty much anything．But Stevenson's idea may inspire a new look at an old problem．Great things can come from what seems like impossible ideas.

Going inside the earth is ________ than going into space.

A．more interesting B．more possible    C．easier            D．more challenging

How deep have we gone into the earth until now?

A．6 miles．         B．4,000 miles． C．7.5 miles．        D．25 miles.

Which of the following is TRUE about David Stevenson's idea?

A．It is an inspiring but not practical idea now．

B．It is a practical proposal that has come into use now.

C．It is a good proposal that will soon be put into practice.

D．It is a false theory that cannot be carried out at all.

What might be the most suitable title for the text?

A．An Annoying Problem for Humans

B．To the Center of the Earth

C．The Mohole Project

D．David Stevenson' s Proposal

It is easier to float in the ocean than it is to float in a swimming pool. Do you know why?

Ocean water is full of salt— and salt water can hold up more weigh than fresh water. See for yourself!

You Will Need:

● 3 cups of warm water

● Measuring cup (量杯)

● Wide-mouthed jar

● Salt

● Spoon

● Raw (生的)potato

You Will Do:

1. Pour 1.5 cups of warm water into the jar.

2. Add 1/3 cup of salt.

3. Stir(搅拌) until the salt is completely dissolved.

4. Add another 1.5 cups of water. Pour it slowly over the back of the spoon into the jar so that the two liquid will not mix together.

5. Gently place the potato into the jar. Do not drop it.

What Will Happen:

The potato will sink— but only halfway!

Why?

Salt water is heavier than fresh water, so it will stay on the bottom. The fresh water will remain on top.

The potato is heavier than the fresh water, but it is lighter than the salt water. That is why the potato will sink halfway down.

1.In the experiment, what should you do right after you pour the water over the spoon?

A．Add the salt to the water.                 B．Stir the salt into the water.

C．Place the potato in the jar.                 D．Pour warm water into thejar.

2.In Step 4 of the experiment, why do you pour the water over the spoon “slowly”?

A．It is easier to see what you are doing.

B．It pushes the fresh water to the bottom.

C．It will keep the water from coming out.

D．It will keep the liquids from mixing together.

3.In which step of the experiment do you add the salt?

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

4.What does the underlined word “gently” mean?

A．Carefully          B．Quickly           C．Secretly           D．Silently