英语必修三第四单元Astronomy:the science of the stars的原文 嗯 忘了把书带回家了 明天学第四单元reading 我需要朗读原文 快

HOW LIFE BEGAN ON THE EARTHNo one knows exactly how the earth began,as it happened so long ago.However,according to a widely accepted theory,the universe began with a "Big Bang" that threw matter in a...