【英语时差8,16】微波炉如何加热食物？2

 Microwaves heat water by jerking the water molecules² around, so to speak. Each water molecule¹ has a slight positive electric charge on one side and a slight negative charge on the other. As microwaves pass by, they exert forces on those charges, first one way, then the other, several billion times per second. These back-and-forth forces turn the water molecules one way, then the other, repeatedly breaking the temporary bonds that water molecules form with each other. It’s a kind of microscopic³ stirring. The result of all this agitation⁴ is more violent random⁵ motion of all the water molecules in the food — in other words, the water gets heated. Microwaves reach all the water in the food at once, so all parts of the food are heated at once. A conventional oven heats food only from the outside, and that’s why conventional cooking takes longer than microwave cooking.

1 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

2 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

3 microscopic   

adj.微小的，细微的，极小的，显微的

参考例句：

• It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。
• A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。

4 agitation   

n.搅动；搅拌；鼓动，煽动

参考例句：

• Small shopkeepers carried on a long agitation against the big department stores.小店主们长期以来一直在煽动人们反对大型百货商店。
• These materials require constant agitation to keep them in suspension.这些药剂要经常搅动以保持悬浮状态。

5 random   

adj.随机的；任意的；n.偶然的(或随便的)行动

参考例句：

• The list is arranged in a random order.名单排列不分先后。
• On random inspection the meat was found to be bad.经抽查，发现肉变质了。