In natural spoken English, prepositions go to the VERY END of the question.
Who are you talking to? What are you looking at?
not To whom are you talking (too formal)
Where do you come from?
In formal written English, preposition goes before Whom / Which.
To whom it may concern, In which city do you reside?
informal prefers end position
For what purpose?
| Example / Question | Positive / Short Answer | Negative / Short Answer |
|---|---|---|
| Who + with? | Who did you go with? | Natural spoken English |
| What + for? | What did you buy that for? | Means: Why did you buy it? |
| Rule | Base / Standard Form | Applied Form |
|---|---|---|
| End Preposition Rule for Spoken English | Place prepositions at the end of the question in spoken English (e.g., "What are you talking about?" NOT "About what are you talking?"). | Who are you waiting for? |
Ask natural daily questions involving prepositions.
"What... for?" means the exact same thing as "Why?" (e.g., "What did you do that for?" = "Why did you do that?").