谁 vs 哪个 (shéi vs nǎge): who vs which one
谁 (shéi) asks for a person’s identity without any set or context, expecting an open answer. 哪个 (nǎge) asks to pick one person or thing from a known (or implied) set. The key difference is that 谁 is an open pronoun, while 哪个 is a determiner that already contains the classifier 个 and points to a limited choice.
Both 谁 and 哪个 can be used to ask about a person, but they operate differently. 谁 is a pure interrogative pronoun meaning 'who' – it does not imply any particular group. 哪个 is a compound of 哪 (which) and the classifier 个 (general measure word), meaning 'which one' – it always presupposes a set (explicit or implicit) from which the answer must be chosen. When referring to a person with 哪个, the noun directly follows (e.g., 哪个老师), and no additional classifier is needed.
When to use each
Use 谁 to ask for a person’s identity when there is no assumed set of possibilities. It is an open question; the answer could be any person. 谁 also works in rhetorical questions and as an indefinite pronoun ('whoever'). For possession, add 的: 谁的 (whose).
Use 哪个 to ask for a specific person or thing from a limited set (either stated or clear from context). 哪个 already contains the classifier 个, so it directly modifies a noun without an extra classifier (e.g., 哪个老师, never 哪个个老师). It can also be used with 的 to mean 'which one’s' (哪个的).
When asking about a person, 哪个 can sound more polite than 谁 because it implies the person belongs to a known group (e.g., in an office). In very formal contexts, 哪位 (nǎ wèi) is preferred over 哪个 for people.
At a glance
| 谁 | 哪个 | |
|---|---|---|
| Question type | Open identification | Selection from a set |
| Set implied? | No | Yes |
| Can precede a noun directly? | No (*谁老师) | Yes (哪个老师) |
| Contains a classifier? | No | Yes (个) |
| Typical answer | A name or description | A choice among options |
Examples
- 谁他是谁？Tā shì shuí?Who is he?Open question; no set assumed.
- 谁谁来了？Shuí lái le?Who came?The speaker doesn’t know who to expect.
- 哪个哪个是你的朋友？Nǎ ge shì nǐ de péng you?Which one is your friend?Implies a visible set of people.
- 哪个你喜欢哪个老师？Nǐ xǐ huan nǎ ge lǎo shī?Which teacher do you like?Directly modifies 老师 without extra classifier.
- 哪个哪个人来了？Nǎ ge rén lái le?Which person came?Valid phrase; 个人 is fine because 人 is the noun.
- 谁谁的手机？Shuí de shǒu jī?Whose phone?With 的 for possession.
Common mistakes
- Using 哪个 to ask 'who' when there is no set (e.g., 哪个是你的名字? should be 你是谁? when asking a stranger’s name).
- Adding an extra classifier after 哪个 (e.g., 哪个个老师). Remember 个 is already inside 哪个.
- Using 谁 as a determiner before a noun without 的 (e.g., 谁老师). Use 哪位 or 哪个老师 instead.
- Thinking 哪个人 is wrong – it is correct and emphasizes 'person' specifically.
FAQ
- What is the difference between 谁 and 哪个 when asking about a person?
- 谁 asks for someone’s identity with no assumption of a set; the answer could be anyone. 哪个 asks to choose from a known group (e.g., pointing to several people). Use 谁 for open questions and 哪个 for picking from options.
- Can I use 哪个 to ask 'who'?
- Yes, but only when you have a specific set of people in mind. For example, 哪个是你的朋友? (Which one is your friend?). For a general 'who', use 谁.
- Do I need a classifier after 哪个?
- No. 哪个 already contains the classifier 个. Say 哪个老师, not 哪个个老师. Do not add another classifier before the noun.
- Is 哪个人 correct?
- Yes, it is a valid and common phrase meaning 'which person'. It is not redundant; it just specifies 人 explicitly. However, 哪个 alone can also refer to a person if the context is clear.