划红精讲：
1. what on earth...
on earth（用于以how， why， what 或 where 开始的问句，表示强调，通常表示问题没有答案或很难回答）究竟，到底；
eg. How on earth did that happen?
那件事到底怎么发生的？
eg. What on earth had Luke done?
卢克究竟做了什么？
eg. Why on earth would he want to go to such a place?
他到底为什么想去那么个地方？
2. be unfamiliar with
不熟知的；不了解的；
eg. I am unfamiliar with the place and the people here.
我在这儿人地生疏。
eg. A foreigner is usually unfamiliar with many customs of a country.
一个外国人通常不熟悉别国的风俗习惯。
3. shut up
（使）住口；（使）闭嘴；
eg. Just shut up, will you?
闭嘴，好吗？
eg. I don't feel like shutting up; I think statements about injustice should be made.
我不想住口，我认为应该发表关于不公正的声明。
eg. A sharp put-down was the only way to shut her up.
对她冷嘲热讽是让她闭嘴的唯一方法。