标签：calculus 相关文章
A review of the guidelines for HIV treatment in poor countries finds priority should go to starting that treatment early. What we learned from a clinical standpoint, as well as a cost-effective standpoint, is that earlier anti-retroviral therapy impr
VOA标准英语2010年(十二)月
There's an important vote coming up in the United Kingdom next week. We mentioned it once before. It's an early or snap election. Though the country's general elections are scheduled to take place every five years, British Prime Minister Theresa May
CNN美国有线新闻2017年7月
Carlos: Did you get your class schedule? Marianne: Yeah. You? Carlos: Yeah. Lets see if we have any classes together. I have PE with Mr. Lopez and social studies with Ms. Walters. How about you? Marianne: I have PE with Ms. Schwartz and social studie
地道美语播客
The cold means that many of us will be turning on our heaters more and more and that means big bills for natural gas, home heating oil and electricity. In some places, the price of natural gas is up 70% over last year and heating oil is up 30%. In up
2005年NPR美国国家公共电台
By Jim Malone Washington 26 April 2007 The divisive issue of abortion is likely to be a major point of debate in next year's U.S. presidential election, thanks to a recent ruling by the Supreme Court. VOA National correspondent Jim Malone reports fro
2007年VOA标准英语（四月）
Ancient Tooth Plaque Reveals Diet Long before the development of agriculture, our prehistoric ancestors had a good knowledge of plants not just for food, but for medicine. Researchers found evidence of this by studying some ancient teeth found in Cen
VOA标准英语2014年(七月)
When you start off coming out of the egg and youre less than, say, 2 feet long and you are in a world full of predators that are loving to crunch on you, then you need to get big fairly quickly. The future seems bleak for this dinosaur. With its life
探索与发现2013年