หรือ

1. Linking Alternatives
หรือ is placed between two or more options to present a choice. It can link single words or entire sentences.
Example: กาแฟหรือชา (Coffee or tea?)

2. Question Particle
When placed at the end of a sentence, หรือ turns a statement into a question, expressing surprise or seeking confirmation. The written form หรือ (rǔue) can occur in questions, including questions followed by a polite particle. The spelling หรือ does not make every such question highly formal or literary. In speech and informal writing, related question forms include เหรอ (rə̌ə) or หรอ (rɔ̌ɔ) instead.

3. Related Forms and Constructions

• หรือ (rǔue): The standard spelling, used between alternatives and in some question-final contexts.
• รึ (rʉ́): A short-vowel, high-tone variant found in speech; register depends on the full utterance and situation.
• เหรอ (rə̌ə) / หรอ (rɔ̌ɔ): Spoken question forms that can express surprise or seek confirmation. Distinguish the construction: These question-particle forms are not the alternative-linking pattern practiced here (e.g., กาแฟเหรอชา does not show that pattern). To link the choices here, use หรือ (or the variant รึ). One way to answer affirmatively is to repeat the main verb or adjective (e.g., ไปเหรอ? - You're going? -> ไป - Yes, I'm going). You can also say ใช่ (châi - correct) to confirm the proposition when that response fits the question and context (e.g., เป็นหมอเหรอ? - Are you a doctor? -> ใช่ - Yes, that's right). Negative answers depend on what is being denied; one possible response is เปล่า (plào - no / nothing), or use ไม่ใช่ (mâi-châi - not so) to deny an identification or proposition, or ไม่ (mâi) + [Verb] to negate a predicate. This includes suitable state predicates, rather than a rigid noun/state/action division.
• หรือว่า (rǔue-wâa): Used to link clauses or suggest a 'second thought' (e.g., 'Or is it that...?').
• หรือเปล่า (rǔue-plào): A question form corresponding to 'or not'. Compare it with ไหม for ordinary yes/no questions: หรือเปล่า checks whether something is so, without necessarily pressing for an answer or requiring a prior assumption. For example, ไปไหม (Are you going? - an ordinary yes/no question) versus ไปหรือเปล่า (Are you going or not? - another way to check the proposition). Tone and context affect the interpersonal meaning. Related forms found in speech or informal writing include รึเปล่า (rʉ́-plào), เปล่า / ป่าว (pào), or even just ปะ (bpà) or ป้ะ (bpâ) (e.g., ใช่ป้ะ - 'Right?'). A short affirmative answer can repeat the predicate; a negative answer can use เปล่า (plào) or ไม่ (mâi) + [Verb].
• หรือยัง (rǔue-yang): Meaning 'or not yet?', this is used to ask if an action is completed. To answer affirmatively, use [Verb] + แล้ว (lɛ́ɛo - already). To answer negatively, use ยัง (yang - not yet) or ยังไม่ (yang-mâi) + [Verb].
• หรือไม่ (rǔue-mâi): A way to say 'or not' often found in written questions; this does not impose a formality rule on every utterance.

4. Common Patterns and Omissions
In declarative 'either/or' statements, Thai speakers often use หรือไม่ก็ (rǔue-mâi-gɔ̂ɔ), meaning 'or else' or 'otherwise'. Closely related is the correlative conjunction ไม่...ก็... (mâi...gɔ̂ɔ...), which is one construction for expressing 'either A or B', rather than a ban on ordinary alternatives joined with a conjunction. Additionally, in casual speech, when asking a choice question using opposites ('Verb or Not Verb'), หรือ can be omitted in a conversational pattern whose alternatives are understood (e.g., ไปไม่ไป - 'go or not go?').