1. There is a book beneath the box.
2. There is a book under the box.
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Which one is correct? Do we have to use 'beneath' or 'under'? On the floor, there is a box. Between the box and the floor, there is a book. In this case, which preposition do we have to use?
2 answers
In both cases, beneath and under both work, but speaking in terms of which sounds better, under would be a better choice as it would make the sentence flow better. However, which one you choose to use is entirely up to you. Just use the word that sounds better to you :) // under and beneath mean the same thing. For your sentence, "On the floor, there is a box. Between the box and the floor, there is a book." I'd recommend removing "Between the box and the floor, there is a book" since this is a confusing sentence. To rephrase your sentence: "On the floor there is a box. There is a book under the box."
Yui is right. Both those prepositions are fine.