老外们真正在用的打招呼方式
Hello!/ Hi!
This is the plain, everyday expression that you should probably use most.
最“平淡无奇”的说法，我们每天用得最多的表达打招呼的方式
Good morning
Say this the first time you see someone in the morning. It sounds nice, but a little bit formal.
你可以在早上第一次见到对方的时候说，听起来很友好，但是会有点儿正式
Morning!
This is a more casual version of "Good morning"
这个听起来就比"Good morning"要随意多啦~
Good afternoon / Good evening.
These are more formal than "Good morning". You might say "Good afternoon" to a customer that you don't know well, or on stage when giving a speech or lecture.
这两个要比"Good morning"还要正式得多！一般会用在你不是很熟悉的客户或者是上台演讲的时候
Hey
Use "Hey" with people that you know well. It's not exactly rude to use with strangers, but it might be confusing. They might think, "Huh? Do I know you?"
这个通常在熟人间使用。如果跟陌生人说Hey，虽然不会说很粗鲁，但是会让人很困惑，“啊？我认识你吗？”
What's up?
This sounds casual and cool. Even though it looks like a question, it doesn't need to be answered.
这个听起来比较随意，酷酷哒！虽然看起来像是个问题，但是并不是真的需要去回答
Sup?
This is a slang version of "What's up?". Use it if you're a teenager or want to pretend that you are one.
这个是“俚语”版的 "What's up?"，一般都是青少年中在用，当然，我知道，你还是个“宝宝”嘛
How are you./ How's it going?
Looks like a question, but sometimes it's not. You can say this to someone instead of "hello", even if you're only passing them by and don't intend to wait their answers.
看起来像个问题，但有时并不是。你可以用它来代替“Hello”，甚至有时你们只是擦肩而过，你也并没有真的想要听到对方的回答
Howdy
This is widly used in Southern America. You might sound like you're pretending to be a cowboy if you use it.
这个在美国西部用得比较多，说的时候感觉自己就像是西部牛仔
Well hello!
Say "Hi" this way when you're surprised to see someone, or if you haven't seen them in a long time. It makes you seem excited.
当你很惊讶地看见一个人，或者你们好久不见了，你觉得特别激动的时候可以这么说
Look who it is!
You can use this when you see someone that you haven't seen in a long time. It sounds really excited.
这个同样用于看到你好久没见的人，非常激动的时候
Yo
This is hiphop slang from the 1980's and 1990's. When you say this, you sound either tough and cool, or silly. It all depends on your personality.
这个源于二十世纪八九十年代的hiphop。你说的时候会显得或是酷酷的，或是愚昧的。当然这个还是得看气质，哈哈！
Greetings!
This is an extremely formal greeting. Robots on TV and movies say "Hello" this way. You can use it to be funny if you're tired of using other phrases
这个是非常正式的问候方式。电视或者是电影中的机器人会用“greets”来打招呼。如果你用腻了其它的打招呼方式的话，你也可以试着用用这个哦~
好啦
看了这么多种打招呼的方式
你Get了几个呢？
下回见面打招呼
不要只说Hello了哈
(李老师)
