1) up to my ears 忙极了

2) couldn't believe my ears 不敢相信

3) music to my ears 听到好消息使你很高兴

4) play it by ear 随行应变

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补充一个美国习惯用语：talk one's ear off。

它的字面意思是:把某人的耳朵都说得掉下来了。这是夸张的说法，它的意思是喋喋不休地说个没完。例句：He talked my ear off about himself. 他没完没了地大谈特谈自己