making chinese sentences,you must pay more attention to the tone (rising is a question, falling is a statement )
as you have known 吗 means an obvious question.
呢 is used like 吗 for example:你的意见呢=说说你的意见好吗？
啊,哦and 啦 just stands for having known something.for example;我知道啦=我知道啊=哦，我知道啦（besides means peevish）
吧means unwilling to do something .for example 好吧，听听就听听啦
