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，练习记笔记技巧和复述。废话少说，下面开始：
1,000-Year-Old Teeth Reveal Diet and Disease
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。
I’m guessing you brush twice a day or aspire to. Our ancestors were a little less diligent. But that’s a good thing for scientists. Because ancient, plaque-coated teeth are like time capsules, preserving early evidence of cavities or even plague DNA.
Now researchers have turned to thousand-year-old teeth from a convent cemetery outside Frankfurt, Germany. And they cleaned ’em, much like your dentist does.
“We used the same dental tools, and collected the calculus from the teeth.” That’s molecular anthropologist Christina Warinner of the University of Oklahoma. Inside that calculus—or plaque—she and her colleagues found tiny bits of pork, bread wheat and cabbage, identified by their DNA. Along with the bugs behind strep throat, bacterial meningitis and an oral strain of gonorrhea. And don’t be too quick to judge. “Nearly all of us still have gonorrhea in our mouth.” Their study is in the journal Nature Genetics. [Christina Warinner et al., Pathogens and host immunity in the ancient human oral cavity]
Some of those bugs were antibiotic resistant too. Because long before penicillin, some microbes produced natural antibiotics to attack rivals. “Your mouth is like a battlefield of bacteria.” So chew on that.