When answering questions I encountered a notify that I should input more than 30 characters. Some questions can be answered use chinese mixture shortly like this post. Should we treat a Chinese character as two latin characters? When I develop website in China, we deal with the problem like that.
It's true that sometimes all you have to answer is a sentence and it works. I've done and seen it on EL&U as well.
But I'd like to ask you to elaborate when you post answers like that. Beginners like to see why a certain expression is more valid than others. If you just post a list of expressions, it's hard sometimes to understand the expressions themselves or to choose, etc... So if possible, add an explanation when it would be helpful, add a note if necessary, etc.
Sometimes they are small things for the poster but very valuable for the reader, and this would also bring you more upvotes. :)