States of Matter
Matter is made of atoms and molecules.
Water, for example, is the H2O molecule.
This means that the molecule of water has 3 atoms.
A water molecule has 2 Hydrogen atoms and 1 Oxygen atom.
Substances like sugar have many atoms in their molecules.
A molecule of sugar has many atoms including carbon, hydrogen and oxygen.
Matter is made of molecules such as H20, which is the water molecule.
Matter can be in one of three states, solid, liquid or gas.
Water and ice are the same substance, but they are in different states.
These states depend on the temperature of the molecules.
When we heat a substance, the molecules move faster and try to take up more space.
When we cool a substance, the molecules move more slowly.
When we cool a substance to its freezing point, it becomes a solid.
In a solid, the molecules move very little.
Their positions are almost fixed.
To be fixed means that their positions don’t change.
If we heat the molecules, they move faster and away from each other.
The solid begins to melt like ice cream on a hot day.
At a certain temperature, a solid begins to change into a liquid.
The temperature at which a solid change into a liquid depends on the substance.
For water, the solid begins to change into a liquid when its temperature rises to above 0 degree Celsius.
For some substances, such as steel, the temperature which it becomes a liquid is much higher.
Steel often melts at around 1370℃.
If we continue to heat a liquid, the molecules move even faster.
At a certain temperature, the liquid begins to change into a gas.
For water, the liquid begins to change into a gas at 100 degrees Celsius.
That is the boiling point of water.
Inside a start, such as our Sun, the temperature is very high.
Everything inside the Sun is a gas.
According to scientists, there are over 65 elements inside the Sun.
These include oxygen and iron.
Over 90% of the Sun is hydrogen gas.
Test Results
Yesterday, there was an important science test.
Lisa, Tom and 20 other classmates took the test.
The test was about the states of matter and how they are different.
There were 25 questions on the text and they had 45 minutes to take it.
Here are some of the test results.
Two students got perfect scores.
The lowest score was 68 out of a hundred.
The average score was 86.3.
Eleven studentsscored higher than average.
Eleven students had below average scores.
Tom missed two questions on the test so his score was 92.
His score was the eighth highest in the class.
Lisa missed two and a half questions so her score is 90.
Her score was tenth highest score.
Her score was 4 points higher than the average score.
Lisa was disappointed with her test results.
She studied hard for the test but she still didn’t do well.
As a result, she plans to study harder for next test.
The next test will be in about two weeks.
Tom was surprised and happy with his results.
He didn’t study hard so his result was better than he expected.
He was also happy that he did better than Lisa did.
Emotions
She‘s screaming because she is really scared.
Something is chasing her so she is screaming for help.
He’s shouting because he is angry.
When he is really angry he often shouts like this.
She‘s sleeping because she’s tired.
Last night she didn’t get enough sleep so today she has no energy.
She’s crying because she’s sad.
She got some bad news a few minutes ago.
She’s smiling because she’s happy.
Her boyfriend just called and he is returning from a long trip.
Hobbies
This man is hiking up a mountain trail.
He is wearing hiking boots and is carrying a pack on his back.
This man enjoys cooking
He attends a cooking class once a week.
This woman enjoys gardening.
She grows flowers， such as roses， and vegetables， such as tomatoes，in her garden.
This boy loves playing games.
He likes all kinds of games including this video game on his computer.
This old couple enjoys traveling.
They take several trips a year often to different countries.
Ready for the Meeting
Oh, there you are, finally.
Yeah, I’m sorry.
Why are you so late?
You were supposed to be here 30 minutes ago.
I got on the wrong subway by mistake.
Why didn’t you call?
I was really worried.
I don’t have my phone.
I left it in the office because I was in such a hurry to get here.
OK, well, you’re here now.
We don’t have much time.
Yes, we'll have to hurry.
The meeting starts in 15 minutes, right?
Yes, it supposed to if everyone gets here on time.
Q: what did he leave in the office?
A:he left his phone in the office.
Q: To hurry means?
A: to go fast.
Did you read my presentation?
Yes, I did.
It’s good, but it’s a bit too long.
I’m afraid there won’t be enough time for questions.
Do you have any suggestions?
Yes, I do.
I think the company introduction can be cut in half.
They know what we do.
OK, I won’t show the video.
It’s about two minutes long.
That’s a good idea.
The video is on our website and it’s not that good anyway.
Q:What she going to do at meeting?
A: She's going to give a presentation.
Q: what she going to cut from their presentation?
A: She's not to going show the video.
Do you have any other suggestions?
Not, I don’t.
I’m sure you will do your great job.
Are you ready?
Yes, I’m ready.
The meet room is on the 21st floor.
OK, let’s go.
Q: What she ready for?
A: She's ready for her presentation.
She's ready to give her presentation at the meeting.
Discussing Test Results
How did you do on yesterday science test?
I did better than expected.
How about you?
I didn’t do very well.
I expected to do better than I did.
What was your score?
I got a 90.
What about you?
I got a 92.
I only missed 2 questions.
Q: How well did she do on the test?
A: worse than expected.
Q: How did she feel about her test result.
A: disappointed.
He did better than expected.
She was disappointed with how she did on the test.
She didn't do as well as she expected.
So you did better than I did.
And I really study for it too.
That’s a surprise.
You usually do better than I do.
Yes, I wasn't careful.
I made one really stupid mistake.
What was it?
I said 90% of the sun is Helium instead of hydrogen.
Wow, there was a stupid mistake.
Q: Why didn't she do well on the test?
A: She wasn't careful enough.
Q: What are Helium and Hydrogen.
A: They are both gases
What was the average score for the class?
Do you know?
The average score was 86.3 and the lowest was 68.
Do you know who got the lowest test score?
No, I don’t.
I don’t know who got the lowest score.
It’s probably a secret.
Did anyone get a perfect score?
I think Ada and Sanjay both got perfect scores.
Yes, they always do well.
I wish I were as smart as they are.
Q: How many students got perfect scores?
A: 2 students got perfect scores
What was the average test score
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