그러게 말이야. (Geu-reo-gae mal-i-ya.) – That’s what I’m saying. / So true.
You may have also heard the abbreviated version of this, where they just say the first part. Check out this commercial for a great example. The first guy raves about the weather and the second guy agrees using the first part of this expression. (The conversation quickly switches into a debate on the speed of a mobile service provider.) Intonation on these is crucial, so you have to get a Korean friend to help you on this one if you want to use it, but you’re going to start hearing it constantly. It’s used so often that you should be able to easily repeat it soon.
“날씨가 참 좋지?” (Nal-sshi-ga cham johji?) – The weather sure is nice, huh?
“그러게 말이야. 산책해야겠어.” – It sure is. We’ve gotta go for a walk.
Talk about used all the time. I can’t believe it! I’ve been teaching Chinese characters for over three years and looking back I’ve realized that I never taught this crucial character. This character for water is used in everything related to water, and the first word is often used with no relation to water whatsoever, simply meaning “level.”