in or into ?

[Zoe2008]

which one is correct ?

please keep this document in or into your file

[Anglika]

Please put the document into your file
Please keep the document in your file

[philadelphia]

Into implies a change of statement. Into means in+to. Ei you are outside and you want to go inside. Eg Come into my world (in that case, you are outside but by the side of getting in(to)).

In would rather mean that something is already inside. No need to move into. Eg Where is your sixter? She is in her bed-room.

Not a teacher at all