陶瓷被用作人工股骨头材料是因为
A.价格低B.耐蚀性好C.耐磨性好D.生物相溶性好E.耐疲劳性好
参考答案:C
解析:[解题思路] 人工陶瓷耐磨性好,故常用作人工股骨头材料。
John was given the same suitcase his father and grandfather ___ with them to school.
A.took
B.had taken
C.were taking
D.would take
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