One reason alfalfa is rich in nutrients is because its roots extend as much as 30 feet into the soil, reaching stores of plant food and water reserves and allowing it to withstand extreme drought.是什么意思_One reason alfalfa is rich in nutrients is because its roots extend as much as 30 feet into the soil, reaching stores of plant food and water reserves and allowing it to withstand extreme drought.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句