Mary blows hot and cold about her job every day, she changes her mind.

玛丽对于工作的事情总是拿不定注意，今天想这样，明天又想那样。

He tends to blow hot and cold.

他可能拿不定主意。

A:Look,the girl is so beautiful and she is smiling at me.

看!那个女孩真漂亮，她对我笑呢。

B:She is so lovely.

她真可爱。

A:I can't agree with you. She's pretty, but she always blows hot and cold.

我不同意你的看法，她很美，但是她总是喜怒无常。