重点讲解：
1. go overboard
做得过分（或过火）；
eg. Women sometimes damage their skin by going overboard with abrasive cleansers.
女性有时因过度使用磨砂膏而损伤了皮肤nMvo_!g++S6XHg7_3。
eg. He has a tendency to go overboard at their parties.
在他们的晚会上，他总是喜欢过分地表现自己PAJbl3PV%qlok=。
2. fed up
厌倦的；厌烦的；腻味的；
eg. He had become fed up with city life.
他已经厌倦了城市生活CQx|kLl!DG(l_A。
eg. I'm just fed up and I don't know what to do.
我就是腻味了，不知道该怎么办oEmGrKuv*jIbsX8Hd;。
3. back and forth
往返；
eg. He paced back and forth.
他来回踱步01qzyHIk3i。
eg. Two boys were in the street, tossing a baseball back and forth.
两个男孩在街上来来回回地投接棒球ESxo%P|VZ!vxLK7!D79。
4. tune out
走神；开小差；漠视；
eg. Whatever you're talking about, children rapidly tune out if you go beyond them.
不管你在说什么，如果孩子们听不懂，就会很快走神nWD=dwyBX6iZ5kOy@u*A。
eg. Rose heard the familiar voice, but tuned out the words.
罗斯听到了熟悉的声音，但没注意听说的是什么%Z.!l~V|rfP!9(=Dsfgj。