blow hot and cold to sometimes like or be interested in something or someone and sometimes not, so people are confused about how you really feel 冷热无常;反复无常;摇摆不定 He's been blowing hot and cold about the trip to Brazil. 他对去巴西这事一直变来变去。 Mary blow hot and cold about her job; every day she changed her mind. 玛丽对于工作的事情拿不定主意，她今天想这样，明天又想那样。