(le) "了” It express something has already been done。它表示已经完成的事情 Eg：我弹了一整天钢琴。（wo tan le yi zheng tian gang qin) ->>>>>>>I have played piano all day (ma)"吗” Place it at the terminal of a general interrogative sentence,the answer ,of course the answer will be "yes" or "no"。 “吗”放在一般疑问句的句末，只需要回答“是的”或“不是”. Eg: 你是学生吗？ 是的。(ni shi xue sheng ma？shi de ) ->>>>>>>Are you student ? yes。 (ba)"吧” Place ti at the terminal of a declarative sentence,to express that something that the speaker is not sure,but the statement content is his subjective idea. 放在陈述句的句尾，表示说话的人不太确定，但是陈述的内容是他的主观想法。 Eg :我好像在哪里见过他吧。 （wo hao xiang zai na li jian guo ta ba ) ->>>>>>>It seems that i have ever seen him somewhere. "ne""呢” It usually follows a noun . meas "what about....."它通常紧跟着名词的后面,表示询问。 Eg：你觉着她的裙子很漂亮，那我的呢？ （ni jue de ta de qun zi hen piao liang, na wo de ne ?)->>>>>>>You thought her skirt is very attractive, then what about mine ? "ya""呀”，It's used for strengthening the expression。Its function is similar to the exclamation mark . 它用来加强语气。它的作用类似于惊叹号。 Eg：这里的风景真美呀! zhe li de feng jing zhen mei ya! ->>>>>>>>>The scenery here is really beautiful !

"le,ba,ma,ne"often used as a question's ending,generally,they don't have some big diffenrence in using.

unilke foreign languages, chinese use not only different tones but also different word at the end of sentence to express our emotions. its hard to say how to use these words at here with several sentences. so if u have interesting about chinese, please ask me, and i'll be glad to tell u all i know.