2.【答案】B【解析】根据下文“They first saw lightning make it when the lightning hit sand on the ground.(他们第一次看到闪电使它,当闪电击中地面上的沙子时。)”可知,他们第一次看到闪电使玻璃,说明他们很久以前就开始使用玻璃了,B项“People began using glass a long time ago.(人们很久以前就开始...
Glass is a unique substance that makes up materials all around us. It is very useful because of all its special properties. Learn about glass and...
The sand commonly used to make glass is comprised of small grains of quartz crystals, made up ofmolecules of silicon dioxide, which is also known as silica. When those molecules are heated to high enough temperatures, the sand melts and loses its crystalline structure, and as it cools it ga...
The process that turns sand into glass is very cool – or rather, we should say very hot. Very, very, very hot as it turns out. Humans have been turning minerals from the earth’s crust into glass for 3,500 years. Find out how it’s done and how it’s evolved – from blowing ...
What is glass?Believe it or not, glass is made from liquid sand. You can make glass by heating ordinary sand (which is mostly made of silicon dioxide) until it melts and turns into a liquid. You won't find that happening on your local beach: sand melts at the incredibly high ...
6.How amazing it is! Sand turns to glass when it Bby the lightning. A. hits B. is hit C. is hitting D. will be hit 相关知识点: 试题来源: 解析 答案见上5.C [解析]考查非谓语动词。 句意:— —格里芬女 士,我们该怎么做才能避免在即将到来的考试中犯 愚蠢的错误呢? — —要更加小心。
How amazing it is! Sand turns to glass when it by the lightning. A. hits B. is hit C. is hitting D. will be hit 相关知识点: 试题来源: 解析 B考查被动语态。 句意:这是多么神奇啊! 沙子被闪电击中后变成玻璃。 句子主语it指代的是 “Sand”.与动词hit之间是被动关系,应用被动语态 陈述事实...
1.Glass is made from sand.2.Stamps are sold in a post office.3.This room is not used very often.4.Are we allowed to park here?5.How does his word pronouce?6.We were woke/woken up by the noise.7.The office was cleaned yesterday.8.The house was painted last month.9.There people...
How is sea glass made...The shards from these various sources have been tumbling around in the water, sometimes for decades, before finding their way onto a given beach at a given time. Over time, nature takes what was once man's garbage and turns it into sparkling natural gems - natu...
1. Smart Glass Smart glass, essentially a privacy solution, is a type of glass that can change its opacity at the click of a button. This type of glass is generally made using ions sandwiched between different glass layers. On the application of electric current, these ions shift positions ...