to be careful
HSK level
小心 is written with 7 strokes (小: 3, 心: 4). The animation replays automatically.
小心 (xiǎoxīn) means 'to be careful / watch out / take care.'
Literally 'small heart' — the idea is that a 'small (attentive) heart' is a cautious one. Used in three main ways. First, as a standalone warning or command: 小心! = 'Careful!' / 'Watch out!' Second, before an object as 'watch out for X': 小心车 = 'watch out for cars'; 小心地滑 = 'caution, slippery floor' (a classic public sign).
Third, as an adjective meaning 'careful / cautious': 他做事很小心 = 'he does things carefully.' Two English contrasts: 小心 is closer to 'careful' than 'careful with' — when followed by an object it implies wariness or danger, not gentle handling. For 'be careful with the glass (it's fragile),' you might say 小心点儿 or 轻一点儿 (gentler). The opposite — 'careless' — is 不小心 (bù xiǎoxīn), used adverbially: 我不小心打破了杯子 = 'I accidentally broke the cup.'
Character by character
Memory hook: 小 (small) + 心 (heart) — keep a 'small, attentive heart' = be careful.
小心 appears in 1 Fluentide podcast episode at natural native speed — each with the full Chinese script, pinyin, and line-by-line English translation.
Browse the full episode library小心!前面有车。
Xiǎoxīn! Qiánmiàn yǒu chē.
Careful! There's a car ahead.
spoken
下雨天,开车要小心。
Xià yǔ tiān, kāi chē yào xiǎoxīn.
On rainy days, drive carefully.
neutral
我不小心把杯子打破了。
Wǒ bù xiǎoxīn bǎ bēizi dǎ pò le.
I accidentally broke the cup.
spoken
请小心地滑。
Qǐng xiǎoxīn dì huá.
Caution: floor is slippery.
written
他做事一直很小心。
Tā zuò shì yìzhí hěn xiǎoxīn.
He's always careful in what he does.
neutral
注意 means 'pay attention to / notice.' 小心 implies caution about danger; 注意 is broader 'be aware of / take note of.' 注意安全 = 'pay attention to safety'; 小心点儿 = 'be careful.' Public signs often use both: 注意安全,小心地滑.
当心 also means 'watch out / be careful,' very close to 小心 but slightly more formal and warning-oriented — common on warning signs (当心触电 = 'beware of electric shock'). In speech, 小心 is more frequent.
担心 means 'to worry.' 小心 is 'to be careful' (action-oriented caution). 别担心 = 'don't worry'; 小心点儿 = 'be careful.' Don't mix them up.
关心 means 'to care about / show concern for (someone).' 小心 is 'be careful.' 妈妈很关心我 = 'Mom cares about me'; 小心车! = 'Watch for cars!'
细心 means 'meticulous / attentive to detail' as a character trait. 小心 is situational caution. A doctor should be 细心 (thorough by nature); a pedestrian should 小心 (careful crossing the street).
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