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?

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?"

lol idk :s

All of the questions are grammatically correct, but some may be more suitable or commonly used than others. Here is an evaluation of each question:

1. "What was used by Chinese?" - This question is grammatically correct and clear, but it can be improved by specifying what aspect you are referring to. For example, "What was used as currency by the Chinese?" or "What was used for trading by the Chinese?"

1-1. "Which was used by Chinese?" - This question is grammatically correct, but it lacks context. Without additional information, it may be confusing or difficult to understand what you are referring to. It would be better to specify the subject or context of the question, such as "Which form of currency was used by the Chinese?" or "Which specific item was used by the Chinese?"

2. "What money was used by Chinese?" - This question is grammatically correct and clear. It asks about the type of money used by the Chinese, which in this case is shells.

3. "Which money was used by Chinese?" - This question is grammatically correct, but it may sound a bit awkward or less commonly used compared to the other questions. It would still be understood, but rephrasing it to "Which type of money was used by the Chinese?" may sound more natural.

4. "What kinds of money was used by Chinese?" - This question is grammatically correct, but it implies that there were multiple types of money used by the Chinese. If you are specifically asking about shells, which was the only type of currency mentioned, it would be better to ask, "What kind of money was used by the Chinese?"

5. "What kind of money was used by Chinese?" - This question is grammatically correct and clear. It asks for the specific type of money used by the Chinese, which in this case is shells.