几月几日(jǐ yuè jǐ rì) - what month and what day (date)? in Mandarin

几月几日 (jǐ yuè jǐ rì) asks for a full date, month and day together, repeating 几 (jǐ), "which number", once before 月 (yuè, "month") and once before 日 (rì, "day"). It is the formal, written-register way to ask "what is the date?", the phrasing on official forms and exam papers.

The order matches how Mandarin always states a date, biggest unit first: month before day, the reverse of the day-month order common in British English. 三月十号 (sān yuè shí hào), "the tenth of March", follows the same month-then-day pattern the question expects an answer in.

In everyday speech, 日 (rì) is often swapped for the more casual 号 (hào), giving 几月几号 (jǐ yuè jǐ hào) with exactly the same meaning; 日 (rì) is the version more likely to appear in writing.