Reading Aloud 2

There are many kinds of machines. Most machines make doing work easier. They do this by reducing how much push or pull is needed to do work. Some machines are simple. They have very few parts.

A lever is one kind of simple machine. It makes work much easier. A bottle opener is a lever. It makes it easier to open a bottle.

An inclined plane is another kind of simple machine. It makes work much easier. The ramp is an inclined plane. It makes it easier to move things into a truck.

The wedge is a simple machine. It makes work much easier. It is really two back-to-back inclined planes. A knife is an example of a wedge. It makes it easier to cut things.

A doorknob and a steering wheel are wheels and axles. The doorknob makes it easier to open a door. The steering wheel makes it easier to turn a car.

Expressions

1. push or pull推或拉
2. lever槓桿
3. bottle opener開瓶器
4. The ramp is an inclined plane.斜道（傾斜的平板）是一個斜面。
5. wedge楔子
6. back-to-back inclined planes背對背的斜面
7. A doorknob and a steering wheel門把手……駕駛盤
8. wheels and axles輪子……軸子