How many people were there?
有多少人？
How many days did you take off?
你休了幾天假？
How many children do you have?
你有幾個孩子？
Please let me know how many are coming, if any.
請告訴我，如果有人要來的話，有多少？
Whether we need more food depends on how many people turn up.
我們是否需要更多的食物，這要視到場人數(shù)而定。