PTE听力口语练习-科学60秒- Laser Pointers

PTE考生目前最大的问题之一就是练习题缺乏。除了有限的基本官方书(PLUS,Testbuilder, OG)之外,就没有题了。很多英语基础不是很扎实的同学很难找到练习材料。墨尔本文波雅思PTE培训学校专门为墨尔本,悉尼PTE考生准备了适合PTE听力阅读练习的科学60秒。各位PTE同学可以练习PTE听力中的summarise spoken text和PTE口语中的retell lecture,PTE听力口语-科学60秒-Frosty Moss练习记笔记技巧和复述。废话少说,下面开始:


60秒科学:most-laser-pointers-are-too-strong

听力内容:

60秒科学节目(SSS)是科学美国人网站的一套广播栏目,英文名称:Scientific American – 60 Second Science,节目内容以科学报道为主,节目仅一分钟的时间,主要对当今的科学技术新发展作以简明、通俗的介绍,对于科学的发展如何影响人们的生活环境、健康状况及科学技术,提供了大量简明易懂的阐释。

Laser pointers are helpful when giving a presentation. Just don’t let the beam hit you in the eye especially when it’s green. The National Institute of Standards and Technology says that nearly 90 percent of commercially available green pointers and about half of red pointers they tested are too strong and violate federal safety regulations.

Green lasers use a shorter wavelength of light than red ones, making them brighter and more dangerous. The darker part of the retina heats up from the green laser’s intense, yet invisible, infrared light, which can cause retinal scarring and even blind spots. Because the damaging wavelengths are invisible, the eye’s natural defense mechanism its eyelid doesn’t close to provide protection.

Airline pilots are well aware of these dangers: in 2011 alone there were more than 3,500 cases of lasers being pointed at aircraft. In July 2012 one unfortunate JetBlue pilot suffered an eye injury when someone on the ground shined a green laser through his cockpit window. Luckily, the flight landed safely. Unluckily, it didn’t land on the person pointing the laser.

–Larry Greenemeier

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