Passport and driving licence? They are the basics for drive (3)
'the basics for drive' is the definition.
I can't judge whether this definition defines the answer.
'passport and driving licence? they' is the wordplay.
'passport' becomes 'id'.
'and' is a charade indicator (letters next to each other).
'driving licence? they' becomes 's' (I can't explain this - if you can you should give a lot more credence to this answer).
'are' is the link.
Can you help me to learn more?
(Other definitions for ids that I've seen before include "Cards to identify the bearers, initially", "Tory".)