farmers needed toboostyields in the fields they had.How this could be done was a challenging question at the time. Yuan wasconvincedthat the answer could be found in the creation of hybrid rice. A hybrid is a cross between...
UNIT 5 WORKING THE LANDReading for Writing英汉对照人教版选择性必修一Unit 5 Using Language.mp3音频:进度条00:0003:40后退15秒倍速快进15秒Chemical Versus Organic Farming化学与有机农业的比较Chemical pesticides and artificial fertilis...