1. How many are there in your family?

Question

1. How many are there in your family?

2. How many people are there in your family?
3. How many members are there in your family?

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Are they all aceptable?
Which one is the most common?

Answer 1

They are all acceptable. No. 1 is most common.

The word "there" could be omitted in each, but it is probably best to leave it. When responding to the question, "There are.." would be the appropriate beginning.

Answer 2

Yes, all three of these questions are acceptable and commonly used to ask about the number of people in someone's family. The most common and straightforward question is "How many people are there in your family?" This question is more commonly used in everyday conversation. However, the other two questions, "How many are there in your family?" and "How many members are there in your family?" are also commonly used and convey the same meaning.