Listening
States of matter
Test Results
对话总结
States of matter
Matter is made of atoms and molecules.物质是由原子和分子构成.
atom 原子 molecule 分子
be made of 由...构成 be made from (制作过程中发生化学变化)
The desk is made of wood.桌子是由木头构成的(扔可看出原材料)
The paper is made from wood.纸是由木头做成(看不出原材料)
A water molecule has two hydrogen atoms and one oxygen atom.一个水分子有两个氢原子和一个氧原子.
hydrogen 氢 oxygen 氧
Substances like sugar have many atoms in their molecules.像糖这种物质,有很多原子在它们的分子中.
substance 物质
与matter 区别,substance 是可数名字 matter 是不可数名词
like = such as 比如.
Water and ice are the same substance but they are in different states.水和冰是同一种物质,但是他们呈现的是不同的形态.
liquid 液体
solid 固体
liquid 和solid 既可以做形容词 也可以做名词
When we heat a substance ,the molecules move faster and try to take up more space.当我们加热一种物质的时候,分子会加速移动,并且试图去占用更多空间.
try to do sth 尝试/设法做某事
take up 占据
space 空间
When we cool a substance ,the molecules move more slowly.
cool 冷却,使变凉. cool a substance
In a solid ,the molecules move very little.Their positions
are almost fixed.在固体的形态,分子几乎不怎么运动.他们的位置基本是固定的.
position 位置
fixed 确定的,固定的
How can we change a solid into a liquid ? 我们如何把固体变成液体?
--To change a solid into a liquid,add heat.
change sth into sth 把...变成...
To change a liquid into a solid ,cool it.把液体变成固体,冷却它
We can change ice into water 我们可以把冰变成水.
The temperature at which a solid change into a liquid depends on the substance.固体变成液体的温度取决于物质.
at a certain temperature 在一定温度下
which 是关系代词,前面加at的原因:
当定语从句中的which 做介词的宾语时,我们就要在which前 加上介词,temperature 需要用介词 at ,at...temperature.
正常语序 A solid change into a liquid at which temperature.
在这种情况下 which temperature 是放在介词后作宾语的
所以不能丢掉介词,也可以放在后边
举例:This is the city in which I lived.
This is the city which I lived in.
The temperature 是
For some substances,such as steel,the temperature at which it becomes a liquid is much higher.Steel often melts at around 1370 degrees Celsius.对于一些物体来说,比如钢铁,变为液态的温度非常高,钢铁通常在1370度左右融化.
For water,the solid begins to change into a liquid when its temperature raises to above 0 degrees Celsius.对于水来说,当温度上升到超过0摄氏度时,由固态变成液态.
raise to 上升到
above 大于,超过
If we continue to heat liquid,the molecules move even faster.如果我们继续加热液体,分子运动的会更快.
continue to do 继续做某事
According to scientists ,there are over 65 elements inside the Sun.
inside the Sun 太阳内部 in the Sun 在阳光下
according to 根据
scientist 科学家 science 科学
over = more than 超过
element 元素
Test Results
The test was about the state of matter.考试是关于物质的状态的.
take the test 参加考试 这里的the 是特指前文提到的test
一般我们说考试 可以用 take a test
be about 关于
Eleven students scored higher than average(n.).是一名同学得分比平均分高.
average 平均的(adj) 平均分(n.)
Lisa was disappointed with her test results.As a result,she plans to study harder for the next test.Lisa对她的考试结果感到很失望,因此她计划要为了下一次考试更努力学习.
be disappointed with 对...感到失望
plan to do sth.计划做某事
study harder 更努力学习 study hard 努力学习
Tom was surprised and happy with his test results.He didn't study hard,so his result is better than he expected tom对他的考试结果感到很惊讶,他并没有好好学习,所以他的结果比预期要好.
be surprised with 对...感到惊讶
be better than 比...好
expect 期望
do...better than 比...做的更好
He did better than Lisa did.她比Lisa做的更好
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