蒸汽喷嘴的作用是（）以及使牛奶形成细密的（）。
参考答案：加热牛奶；奶泡
Tom got a full mark in the English final exam, so his parents were very _____.[ ]
A. impressed
B. impress
C. impressing
D. to impress
对先天性肾盂输尿管交界处狭窄最具确诊意义的检查是（）
A.核素肾图
B.肾动脉造影
C.IVP或逆行造影
D.B超
E.皮肾穿刺造影
