When I do not understand grammar, I do not know where to look it up. This leads me to go wandering the wild internet in search of answers.
Korean Grammar Plus is one such site. I “liked” their Facebook page, but I admit there are so many ads on the website that I find it difficult to use. Still … way to make grammar flashcards look pretty!
There are other sites that I use for grammar reference. Many have been mentioned in earlier posts. Of course, Wikipedia and Wikitionary are sources I use.
I tend to run to my bookshelf for “Korean Grammar in Use” or “Mastering Conversational Korean”.
Korean Grammar Dictionary
Of course, if it is related to English grammar, I am happy to visit Grammaropolis and Oxford Dictionary among others.
What do you use for Korean grammar reference?
Hanguk Babble 
So you do know where to look up. I have a Korean grammar dictionary written in simple Japanese as a reference. I think internet is convenient but books are more reliable and trustworthy. I use both.
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