北师大版高中英语模块7--Unit 20 New Frontiers 2

[00:01.56]Gunpowder¹
[00:03.47]Gunpowder was invented by the Chinese
[00:05.73]in the eighth century AD.
[00:08.28]Early Chinese scientists discovered
[00:10.64]that they could make an explosive substance
[00:12.76]by mixing sulphur,charcoal and saltpeter.
[00:16.76]Gunpowder was used in warfare²
[00:18.93]and led to the development of many different
[00:21.00]kinds of weapons.
[00:22.77]For example, rockets carrying an explosive
[00:25.28]shell of gunpowder could be launched
[00:27.98]at enemy soldiers from a bamboo tube.
[00:32.08]The Compass
[00:33.66]The ancient Chinese noticed
[00:34.96]that certain kinds of metals,
[00:36.95]like iron ore, usually aligned³ themselves
[00:39.39]in a north to south position.
[00:41.84]By the third century,
[00:43.17]they had started making the first,
[00:44.84]simple compassesby floating small pins
[00:47.92]of magnetic metal in bowls of water.
[00:50.74]By the eleventh century,
[00:52.11]the Chinese were using sophisticated
[00:54.05]compasses to navigate⁴ their ships at sea.
[00:57.90]In the West magnetism⁵ was not discovered
[01:00.42]until the fifteenth century.
[01:02.65]Until this time, European sailors
[01:04.83]were still navigating⁶ by the stars.
[01:06.56]

1 gunpowder   

n.火药

参考例句：

• Gunpowder was introduced into Europe during the first half of the 14th century.在14世纪上半叶，火药传入欧洲。
• This statement has a strong smell of gunpowder.这是一篇充满火药味的声明。

2 warfare   

n.战争(状态)；斗争；冲突

参考例句：

• He addressed the audience on the subject of atomic warfare.他向听众演讲有关原子战争的问题。
• Their struggle consists mainly in peasant guerrilla warfare.他们的斗争主要是农民游击战。

3 aligned   

adj.对齐的，均衡的

参考例句：

• Make sure the shelf is aligned with the top of the cupboard.务必使搁架与橱柜顶端对齐。

4 navigate   

v.航行，飞行；导航，领航

参考例句：

• He was the first man to navigate the Atlantic by air.他是第一个飞越大西洋的人。
• Such boats can navigate on the Nile.这种船可以在尼罗河上航行。

5 magnetism   

n.磁性，吸引力，磁学

参考例句：

• We know about magnetism by the way magnets act.我们通过磁铁的作用知道磁性是怎么一回事。
• His success showed his magnetism of courage and devotion.他的成功表现了他的胆量和热诚的魅力。

6 navigating   

v.给（船舶、飞机等）引航，导航( navigate的现在分词 )；（从海上、空中等）横越；横渡；飞跃

参考例句：

• These can also be very useful when navigating time-based documents, such as video and audio. 它对于和时间有关的文档非常有用，比如视频和音频文档。 来自About Face 3交互设计精髓
• Vehicles slowed to a crawl on city roads, navigating slushy snow. 汽车在市区路上行驶缓慢，穿越泥泞的雪地。 来自互联网