影响玻璃黏度的主要因素有哪些？
参考答案：
影响玻璃黏度的因素主要有化学组成和温度，在转变温度范围内，还与时间有关。
The young tennis player has often ________ against famous players, but so far he has always failed. [ ]
A．beat
B．raced
C．competed
D．fought
电磁流量计的测量管必须在任何时候都是完全注满介质的。（）
