举例说明它的用法?

问候：
in greetings：What's up, dude?
感叹：
as an exclamation: Whoa, Dude!
同情：
commiseration: Dude, I'm so sorry.
揶揄：
to one-up someone: That's so lame, dude.
同意、惊奇或讨厌：
as well as agreement, surprise and disgust: Dude.
--realdude的马甲