化学消泡剂应具备哪些特点（）.
A.具有较低的表面张力
B.具有亲水性
C.对人、畜无毒
D.来源方便
参考答案：A, B, C, D
与老师沟通的艺术？
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—Chinese writer Mo Yan has won the 2012 Nobel Prize in literature.
—______
A．I think so.
B．That’s all right.
C．That’s a good idea.
D．I’m glad to hear that.
