The once radical notion that birds descended from dinosaurs——or may even be dinosaurs， the only living branch of the family that ruled the earth eons ago——has got stronger and stronger since paleontol
As you read this， nearly 80，000 Americans are waiting for a new heart， kidney or some other organ that could save their life. Tragically， about 6，000 of them will die this year——nearly twice as many p
Scientists have known since 1952 that DNA is the basic stuff of heredity. They’ve known its chemical structure since 1953. They know that human DNA acts like a biological computer program some 3 billi
101. What is it _____ his daughter needs most?A. what B. which C. that D. if102. _____ was very ______ that little Jim wrote the letter.A. It, careful B. It, carefullyC. He, careful D. He, carefully10
本期主题【中国传统婚礼】Traditional Chinese wedding is the essence ofChinese culture. Chinese ancestors believed thatdusk was the luckiest time in a day, so they held thewedding at dusk. Chinese are fond of red c
本期主题【毛笔】The brush pen is a traditional Chinese tool of writing and painting. Chinese people have used the brush pen to write or paint for thousands of years. There is a legend about Meng Tian’s creati
本期主题【大学生就业】The employment of college students is in a dilemmacalled “unemployment upon graduation”,aphenomenon which was once far from collegestudents in China.With the development of societyand econo
本期主题【《西游记》】Journey to the West is one of the Four Great Classical Novels in China.Published first anonymously in the 1590s during the Ming Dynasty，and even though there is no direct evidence of its au
本期主题【春运】The Spring rush is due to the traditional idea of Chinese people and the massive flow of labor force in society.In China, the Spring Festival is the most important traditional festival.However
本期主题【全球气候变暖】Global warming, a natural phenomenon,has been aheated topic in recent years. Global warming willredistribute global rainfall, make glacier andpermafrost melt and sea level rise, which not