nǐ nǎlǐ bù shūfu?
What hurts you?
一天吃几次?
How many times a day?
一天 (yì tiān) means 'one day', 吃 (chī) means 'eat/take', 几 (jǐ) means 'how many', and 次 (cì) is a measure word for times. The phrase asks 'One day take how many times?'
一天吃几次药?
yì tiān chī jǐ cì yào?
How many times a day do you take the medicine? — More specific by adding 'medicine' (药).
你一天吃几次?
nǐ yì tiān chī jǐ cì?
How many times a day do you eat? — More conversational with 'you' (你) and without 'medicine'.
我一天吃几次药?
wǒ yì tiān chī jǐ cì yào?
How many times a day should I take the medicine?
你一天吃三次。
nǐ yì tiān chī sān cì.
You should take it three times a day.
Appropriate
Avoid when
You say '一天吃几次?' (yì tiān chī jǐ cì?). It literally means 'one day eat how many times?' and is used for medication.
It is pronounced 'yì tiān chī jǐ cì?'. Note the tone changes: yì (4th), tiān (1st), chī (1st), jǐ (3rd), cì (4th).
Use it when asking a medical professional how often to take medication per day. It is not used for general eating frequency.
Tomyo
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