下列可用于土壤消毒来防治苗木立枯病的是()。
A.五氯硝基苯
B.代森锌
C.生石灰
D.多菌灵
参考答案:A, C
—Sorry, I have to ring ________ now. It's time for class.
—OK, I'll call back later.
何谓“三丝“?