她的品味变化无常，上个月还喜欢古典音乐，现在却迷上了摇滚。

Her ___fickle tastes changed from classical music last month to rock music now.

他的情绪变化无常，一分钟前还开心，现在却生气了。

He has a ___fickle mood—happy one minute and angry the next.

她的心情像天气一样多变，让人难以捉摸。

Her mood is as ___fickle as the weather, always changing unpredictably.