其耐磨性最高的纤维是()。
A.锦纶
B.羊毛
C.涤纶
D.氯纶
参考答案:A
一 Will it take me long to get to the Sunshine Hotel?
— No, it _____ take you long. It's not the rush hour now. [ ]
A. shouldn't
B. shan't
C. mustn't
D. needn't
铸造的特点:(),适应性广,铸件表面质量差。