A:牛耕出现在春秋时期
B:明清时期出现了曲辕犁
C:汉代出现了二牛抬杠的耦犁
D:东汉时出现了较轻便的一牛挽犁
通过化学课的学习,成语“细水长流”可理解为( )
— Did you listen to the program yesterday?
— Yes. I can't believe I heard her singing ______ the radio.