硬度愈硬的铸铁,其脆的程度()。
A、高
B、低
C、不受影响
D、不高不低
参考答案:A
It ______ we had stayed together for a couple of weeks ____ I found we had a lot in common.
A.was until; when
B.was until; that
C.wasn’t until; when
D.wasn’t ;that
静叶可调式轴流风机加油时间为()个月一次。
A.半;
B.1;
C.2;
D.3