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?

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.

1. If you want to buy books, you would typically have to go to the 4th floor. (This is assuming the shopping mall has multiple floors and designated sections for different types of products.)

2. On which floor can you buy a shirt? The answer would depend on the layout of the shopping mall. If there is a specific floor dedicated to clothing stores, you would need to go to that floor. Let's say, for example, you can buy a shirt on the 3rd floor.

3. Where can you buy shoes? Generally, shoes are available on the first floor of a shopping mall. However, it's always best to check the directory or ask for assistance to ensure the specific location.

4. At which store can you buy shirts and ties? You can usually find shirts and ties at a clothing store. Some stores may specialize in ties, known as tie stores, but it is common to find a variety of ties along with shirts in a clothing store.

5. In a shopping mall, there are numerous shops or stores. It is possible to have a hat shop in a shopping mall. However, the existence of a hat shop would depend on the specific mall and its tenants. It's recommended to consult the mall directory or inquire with mall staff to find out if there is a hat shop.

6. Do you have a CD shop? Or do you buy CDs at a bookstore? Music CDs, lecture CDs, etc. CD shops used to be common, but with the rise of online music platforms, they have become less prevalent. However, you may still find some stores that sell CDs, such as music stores or electronics stores. Alternatively, you can often find a selection of CDs at a bookstore, particularly in the music or media section.

7. On which floor can you buy bags? On what floor can you buy bags? Both expressions are grammatically correct. You can use either "on which floor" or "on what floor" to ask about the floor where bags are available for purchase. The answer would depend on the specific shopping mall, so it's best to consult the mall directory or ask the staff for the exact location.