单词:reverse circulation gravel pack technique
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Transcript This is Scientific American's 60-Second Science, I am Cynthia Graber.This will just take a minute. Physicists at the Brookhaven National Laboratory have been able to send information ahead of particle beams racing at nearly the speed of li
If you are like many language students, you might have a problem with procrastination. Perhaps you are slow to do homework or study for a test. Maybe you do not like to study or you become distracted while studying. Whatever the case may be, learning
倾听音乐:Forward And Reverse 虽是英文,但音乐无国界。它诉的是情,听起来却冷冷清清,仿佛清晨起来照铜镜,发现自己满面愁容。思念已满溢,恍惚间想起昨夜小寐,忽疑君至,却是琉璃火,
By Carol Pearson Washington 08 January 2008 New technology makes surgery safer, shortens recovery time and leaves no scars. Both physicians and patients are pleased with the results. VOA's Carol Pearson has more. Maria Viruet recently had her gallbla
Vacationing on the island of Oahu, we were waiting in our tour bus for some stragglers to show up. A man, obviously not with our group, approached the bus and was about to board. How would our driver handle the situation, we wondered. Straight-faced,
今天我们要学的词是 circulation. Circulation 有发行量的意思。美国皮尤研究中心的报告说,报纸虽然不会马上消失,但是,The declines in daily newspaper circulation are unprecedented. 日报发行量的降低是闻所