硬质合金是用粉末冶金法制造的合金材料,由硬度和熔点很高的碳化物和金属粘结剂组成。()
参考答案:对
We were all very much attracted by the beautiful scenery________we set foot in the village.[ ]
A.quickly
B.suddenly
C.finally
D.immediately
脑瘫是一种静止性脑病,原因是()
A.出生后不会发病
B.脑损伤不会进展
C.患儿在各个阶段的发育均落后于同龄人
D.受累个体会出现静止性震颤
E.EEG显示背景节律异常