vacillate
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/ˈvæsəleɪt/
🇬🇧
/ˈvæsəleɪt/
to keep changing your mind about something, especially in a way that can be frustrating to others
He kept vacillating about whether to take the job or not, which was starting to frustrate his colleagues.
彼は仕事を受けるかどうかを常に揺れ動かし続け、それが同僚たちをイライラさせ始めた。