Yet
‘Yet’ is used to talk about something which is expected to happen. It means ‘at any time up to now’. It is used in questions and negatives.
Have you finished your homework yet? The speaker expects that the homework will be finished.
I haven’t finished it yet. I’ll do it after dinner.
‘Yet’ usually comes at the end of the sentence.
- See more at: http://learnenglish.britishcouncil.org/en/grammar-reference/just-yet-still-already#sthash.afjl8aop.dpuf