Ju : Can be used when you want to state something thats "true, obvious for yourself". For example: You say: 1+1=2. Someone tells you, stop saying that, its not. Then you can reply: Men jag har JU rätt. Emphasizing that you are infact, right. Nog : Can be used for probably and enough. For example, if we look at ex 1, one person can reply back with "Han har NOG rätt". Which translates to he is probably right. Another example can be a mother telling her child "Nu är det NOG!", in this sentence it means it´s enough! Åt : Can mean at or towards. It´s also the past tense of the verb "äter". "Han skrattade ÅT mig" - He laughed at me "Jag sa ÅT dig att sluta" - I told you to stop Jag ÅT makaroner i förra veckan" - I ate macaroni last week

Thank you Eva!

"Nog" can also be translated with "probably": Det kan nog vara sant.