啊 （a）- modal particle ending sentence, showing affirmation, approval, or consent

我的车不需要排队阿
You don't have to queue for my car.
真漂亮啊！
How beautiful!

把 （ba） -  indicating a suggestion or a rhetorical question

把刀给我
Give me the knife.
他把果汁喝完了
He drank all the juice.

吧 (ba) - used while suggesting something

我帮你吧
Let me help you.
给我点儿纸吧。
Can you give me some paper?

了 (le) - used to indicate an action that is complete

吃饭了吗？

Have you eaten?

昨天我买了一个新电视

Yesterday I bought a new TV.

 

吗 (ma) - for question

他是你爸爸吗？
Is he your father? 
我们走了吗？
Shall we go?

呢  (ne) - for questions

我很好，你呢？
I'm good, what about you? 
这些东西呢？
What about these things?