下列属于气体振动而发出声音的是( )
A:叮咚的鼓声
B:哗哗的流水声
C:隆隆的炮声
D:悦耳的歌声
—What's your New Year's resolution, Dave?
—I'm going to exercise more _______.
根据“求同存异”、“小球转动打球”、“伙伴关系”等内容提炼出一个最恰当的学习主题是( )