Passage One Animal life first appeared on the earth about 400 million years ago. Through the passing millennia, thousands of animal species have come and gone. Until recently, this process was gradual, the result of changes in climate, in habitat, or in the genes of the animals themselves. ...
【题目】阅读理解Animal life first appeared on the earth about 400 million years ago. T hrough the passing millennia, thousands of animal species have come and gone. Until recently, this processwas gradual, the result of changes in climate,in habitat, or in the genes of the animals ...
Female Student: So, you mean, that's it. There's no way we can tell when life first appeared on earth. Professor: Well, there might be, let's think about this a minute.If no earlier rocks on earth could have survived with their fossil records intact.Is there anywhere else we could...
The Earth is like our mother.She gives live to all the living things on the Earth.And she provice us with air、food、water and other things we need for living.Once she was beautiful ahd rich.But mow she is crying, becacuse she is becoming dirtier and dirtier, poorer and poorer. It'...
aThe habitat of life forms on earth has been the entire planet, conveniently dividing the world into the birds of the air, the fish of the sea, and the creatures of the land. The evolutionary process also created sea-dwelling mammals who appeared to reverse the process of evolution as they...
当地球上的环境剧变时 a tie that would be their undoing when conditions on Earth... 这种联hearts;系hearts;将使它们毁灭 radically changed. (3亿年前) 在石炭纪 During the period known as the Carboniferous, 地球各大hearts;陆hearts;合为一体 Earths great land masses merged, 超级大hearts;陆hearts;...
Suddenly,three boys in his neighborhood appeared and 44 him. Todd,the biggest one,pulled his Umbrella Hat off his head. “What?s THIS?” he asked. “It?s an Umbrella Hat. You can wear it on rainy days and ?” Garth said. The boys 45 , “Will anyone wear that stupid thing?” Tod...
Similarities between terrestrial planets at the time life appeared on EarthVenus, Earth, and Mars differ in size, distance from the Sun, atmospheric composition, and ambient conditions. However, during the first 500 Ma after their formation—approximately 4.56 Ga ago—they probably had comparable ...
A.the human body has changed compared with human first appeared on earth B.the way we live has changed a little C.our body can’t deal with the changes in life style D.the way we live today is proper for the human body 3.What is the main cause mentioned in the article why people...
By the time she reached the Chicago Columbus Hospital on April 18, 1917, she appeared thin, bent, and frail, relying on a cane for support as she struggled to walk. The doctors quickly recognized that her malaria had worsened significantly and insisted on immediate treatment. Although the ...