所谓“四头四尾”即家头窖尾、(),是对客家妇女吃苦、勤劳、持家的真实写照。
A、地头屋尾
B、田头地尾
C、灶头灶尾
D、针头线尾
参考答案:A, B, C, D
_____ have you been swimming? For five years.
A.How many times
B.How long
C.How often
D.How much
简述镁合金的主要优缺点。