Question

1. What was used by Chinese?
- Shells were used by Chinese.

1-1. Which was used by Chinese?
- Shells were used by Chinese.


2. What money was used by Chinese?
- Shells were used by Chinese.

3. Which money was used by Chinese?
- Shells were used by Chinese.

4. What kinds of money was used by Chinese?
- Shells were used by Chinese.


5. What kind of money was used by Chinese?
- Shells were used by Chinese.
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Which questions are suitable and grammatical?

Answer 1

The answers would be better in active voice rather than passive voice.

The Chinese used shells.

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You use "which" if there's already a choice between or among things that's made clear in previous sentences or in a picture.

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A better phrasing for questions 2 and 3 is this: "What did the Chinese use for money?"

Answer 2

lol idk :s