河北加拿大版初中英语--Lesson 30

Lesson 30:
[00:03.21]Danny the "Dry-o-saur"!
[00:07.58]Danny,Jenny and Brian stand in front of the class.Everyone laughs.
[00:15.23]Danny is wearing his swimsuit!"Okay,everyone!"says Jenny.
[00:22.67]"We are going to show you an interesting experiment.Danny sits down.
[00:30.62]Brian puts water into the jar.
[00:35.19]He puts the card-board on top of the jar.
[00:40.33]He puts his hand on the cardboard¹ and turns the jar upside² down.
[00:47.46]Then he holds the jar above Danny's head.
[00:52.53]"Next,Brian will take his hand off the cardboard,"says Jenny.
[01:00.29]"Now,you know why I'm wearing my swimsuit,"says Danny
[01:06.74]"Are you ready,Danny?"
[01:09.90]"I guess so.""Danny's theory is that he will now get wet,"says Jenny."
[01:19.15]Is he right,class?""Yes,I think so!" says one student.
[01:26.31]"No,I don't think so says Brian.Brian takes away his hand.Brian's right!
[01:35.09]"Are you surprised,class?"asks Jenny.
[01:40.94]"Examine the jar and the cardboard.
[01:45.80]We have discovered that cardboard can hold the water in.
[01:53.03]What are your conclusions? Why didn't Danny get wet?"
[01:59.80]"Maybe you used glue says one student."No,that's not it!
[02:08.76]Brian,can you explain?"say Jenny."The air pushes up on the cardboard,"says Brian.
[02:19.02]"It's like water pushing up on a boat
[02:23.70]The force is strong enough to hold the water.
[02:29.55]Air is stronger than I thought!
 

1 cardboard   

n.硬纸板，卡纸板

参考例句：

• She brought the shopping home in a cardboard box.她将买的东西放在纸箱里带回家。
• There is a sheet of stiff cardboard in the drawer.在那个抽屉里有块硬纸板。

2 upside   

n.上侧，上段，上部

参考例句：

• The children hung the picture upside down.小孩把画挂倒了。
• If you turn the envelope upside down, the key will fall out.你如果把信封倒过来，钥匙就会掉出。