Question

1. If you want to buy books, to which floor do you have to go?
- I have to go to the 4th floor.

2. On which floor can you buy a shirt?
- I can buy a shirt on the 3rd floor.

3. Where can you buy shoes?
- On the first floor.

4. At which store can you buy shirts and ties? - At a clothing store.
(Can we buy ties at a clothing store? Or do you have a tie store where you can buy a variety of ties.)

5. In a shopping mall, there are numerous shops or stores. Do you have a hat shop in a shoppingg mall?

6. Do you have a CD shop? Or do you buy CDs at a book store? Music CDs, lecture CDs, etc.

7. On which floor can you buy bags?
On what floor can you buy bags?

(Which expression do I have to use, 'which' or 'what'?) Suppose the shopping mall is a four-story building.

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I have posted questions and answers. Are the expressions grammatical? Would you check the expressions above?

Answer 1

All look good if you correct the spelling of "shopping" in sentence 5.

http://www.englisch-hilfen.de/en/words/which_what.htm
Explanation of the difference between "which" and "what."

And, yes, you can buy ties in a clothing store. Sometimes there are specialty shops around -- selling only ties or only sunglasses or only hats, etc. But most of the time, the clothing store is just fine.