"The indirect object answers the question “To whom?” or “For whom?” the action of the verb is performed." For example:
- He gives María the book.
To whom does he give the book?
IO = María
- He buys me flowers.
For whom does he buy the flowers?
IO = me
I would like to know why in sentence number 1 we ask to whom and not for whom, and why in sentence number 2 we ask for whom and not to whom. In other words, how do I know when to ask to whom and when to ask for whom in order to find the indirect object.