DiceAnna Nolan’s little ditties might help you remember some of those tricky grammar points. This one is not only difficult for non-native speakers!

‘WITH ME’ VERSUS ‘WITH I’
You must never even try
Saying, “Come with Greg and I”,
For it’s always – you will see –
Always, “Come with Greg and me”.

PS You might like to take a closer look at Anna’s fantastic website: http://flaming-english.com