英语博客-北美风情 157、Heads up!

（单词翻译）

　　This week we’re looking at expressions used for sharing information with people when you are trying to help them out. We talk about which expressions are casual¹, which are formal, and which can be used in different situations. All of the expressions are used often, so listen here and learn how to use them correctly.

　　Maura:  So if we say that I gave my friend a heads up about the test, it means that I told her about the test, or I warned her about the test, before it happened so that she could prepare and be ready for the test.
Harp:  Exactly. And the possible origin for this expression comes from baseball.
Maura:  Like so many American expressions.
Harp:  Exactly. So at a baseball game, when someone yells² heads up, it’s because a ball is coming towards you. So you put your head up to see the ball so you can move out of the way and so it doesn’t hit you.
Maura:  Right. So if you think about it, when that person yells, heads up they’re giving you a warning that the ball is coming.
Harp:  Exactly.