1、轻浮
...fickleness 变化无常flightiness 轻浮volatility 挥发性 ...
flightiness [ 'flaitinis ]
n.the trait of acting unpredictably and more from whim or caprice than from reason or judgment"I despair at the flightiness and whimsicality of my memory"
同义词：arbitrarinesswhimsicalitywhimsywhimseycapriciousness