oufeimaiSeptember 17, 2010, 08:19 PM
Actually 不简单 can also mean "remarkable", "marvelous", so all of these phrases' meaning is similar -- it's in the usage and connotation that they differ. I'm looking for some examples of those differences.
你说得对！Here are some examples:
2. 你会说八种语言？真是太了不起了！（with a strong sense of suprise and admire. while 真不简单 is not as strong as 了不起。）
Besides, if it's negetive, 一般说“没什么了不起的！” or "这有什么了不起的！" （There's nothing special）.
Hope that helps! :)