Ugh, so many words to remember... Also, how can ihr mean so many different things? German is crazy!
I know, it can be a bit confusing at first, especially when you can't see it written down. Luckily for you, I’m going to break this down into a cute little list:
For the grammar-thirsty folks
If you haven't noticed, we have three different words for you:
Informal → du
Formal → Sie
Plural → ihr
you can also be an object, so we also need the accusatives:
I love you. → Ich liebe dich.
I love you. → Ich liebe Sie.
I love you. → Ich liebe euch.
Finally, we should also think about the datives:
I help you. → Ich helfe dir.
I help you. → Ich helfe Ihnen.
I help you. → Ich helfe euch.
The next time someone asks "How do you say 'you' in German?", you should say:
Du, Sie, ihr, dich, dir, Ihnen, or euch... it really depends.
And as you saw in the table above, ihr can also mean your, her and their!