气液两相达到平衡状态时,气液两相的()。
A.温度相等
B.温度不相等
C.平均分子量相等
D.平均分子量不相等
参考答案:A
Though the key was pressed, nothing ______ on the screen.
A.appeared
B.was appeared
C.appears
D.is appeared
义齿影响发音的因素有()
A.腭侧基托形态
B.前牙长度
C.覆覆盖
D.前牙位置
E.以上都对