“挖掘机”的四种英文说法

已推送过的原版书

，我们提到了挖掘机的三种常用说法：excavator、digging machine 和 shovel。


今天的推送中，能看到它的第四种说法 —— digger。单纯从难易程度上来看， digging machine 和 digger 应该是最简单的。但是对自己稍有要求的学习者，也应该记住 excavator 和 shovel，毕竟，它们也并不难记。


anyway，阅读今天的推送，看 digger 出现的一个语境，顺便了解一点粗浅的科学知识吧。

Simple machines 

When a giant rock blocks your path, you need the power of a digger to push it aside. Machines work by turning small forces into big ones. Even complex machines are often made by linking together smaller, simpler devices. These include levers, gears, wheels, and screws. While some machines make forces bigger, others make things go faster. 

▸ digger 挖掘机

▸ lever 杠杆

▸ gear 齿轮


MORE FORCE 

A lever is a long rod that gives you extra pushing or pulling force. The longer the lever, the more force it gives you. A seesaw is an example of a simple lever. If you sit on the end of a seesaw, you can lift someone much heavier than you are, as long as you sit further away from the balancing point. Crowbars, hammers, and many other simple tools also work like levers. 


If you had a lever big enough, you could lift the world. But the lever would need to be about 100 million, trillion km long!

▸ rod 杆，竿，棒

▸ crowbar 铁撬棍


SIMPLE LEVER 

A seesaw has a long, flat board that balances on a support point called a fulcrum. A small force at one end can lift a big weight at the other end.

▸ fulcrum 支点


MIGHTY MACHINE 

This digger's arms use levers to lift heavy loads. Giant tires spread the weight over a large area to stop the digger sinking in mud.

▸ arm 臂状物