过共析钢的淬火加热温度宜选择AC3以上（30-50）℃。
参考答案：错
He ______ listen to pop music, but now he ______ watching Beijing Opera. [ ]
A. used to; is used to
B. used to; used to
C. is used to; used to
D. is used to; is used to
葡萄胎（）
A.血清降钙素（CT）升高
B.β2-微球蛋白升高
C.hCG升高
D.本-周蛋白升高
E.铁蛋白降低
