I didn't think maths ______ important at that time. [ ]
A. is
B. were
C. are
D. was
答案:D
皮带传动压紧轮正确安装位置是()。
A、松边
B、紧边
C、都可以
糖尿病急性并发症主要包括糖尿病酮症酸中毒以及( )。