A:音调
B:方言、土语
C:音色
D:响度
–Listen! Someone is playing ______ piano.
–Wow! What beautiful music! I like it very much
圆:x2+y2﹣4x+6y=0和圆:x2+y2﹣6x=0交于A,B两点,则直线AB的方程是( )
注意摆绳的长度不等于摆的长度,____是指从支架到____的距离。