I mentioned in a previous post that you can often tell if a Mandarin sentence is a question because it will end in 吗 (ma). (Similar to ka in Japanese)
But of course there are other words that indicate a question just by being there. Here are the common ones:
什么 (Shén me) – this is pretty generic but basically means "what"
为什么 (Wèi shén me) – this extends 什么 to become "why"
怎么 (Zěn me) – this is close to "how"
哪里 (Nǎ lǐ) – is "where"
谁 (Shéi) – is the equivalent of our "who"
There are several ways of asking how many of something:
多少 (Duō shǎo) – is literally "how many"
One of the things I find odd with 多少 is that it's also used like we use "how much". For example:
多少钱？(Duōshǎo qián?) means "how much money?" but is literally "how many money"
Another common way to ask how many, is to use:
This one is normally followed by a measure word. A common example is:
几个马？(Jǐ gè mǎ?) – this is "how many horses?"
几个爸爸？(Jǐ gè bàba?) – this is "how many fathers?"
The typical answer is just the count and the measure word:
八个爸爸。(Bā gè bàba.) – in this case, eight fathers.
This character 几 (Jǐ) is an odd one as when it's not used in a question, it's often a synonym for "several".