Erique

Hi there,

I've got some sentences, which have to be grammatical according to an article I read, but I am not really sure about that.

What is your opinion about it?

a. Abby was talking, but I don’t know who to.
b. They were arguing; God only knows what about.
c. A: She got a package in the mail. B: Really? Who from?
d. He’ll be at the Red Room, but I don’t know when till.
e. Bees are getting into the house, but we can’t figure out where from.

My own mother tongue is Dutch, and I'd like to have some opinions of native speakers of English.

Bij voorbaat dank!

MikeL

All these sentences have a similar structure; they contain a preposition [to, from, about...] combined with an interrogative pronoun or adverb [who, where, what...].
In formal or literary English it is considered more appropriate to place the preposition in front of the interrogative word:
... I don't know to whom.
...about what.
...From whom?
etc.
However, in spoken English this "rule" is almost always ignored, and the preposition is placed at the end of the sentence. It is not very elegant, but it can't really be considered ungrammatical. My advice: if you are writing (or speaking) in a very formal context, put the preposition first. In ordinary conversation do what everyone else does, and use the preposition to end the sentence with!