Mandarin Potential Complements: 听不懂, 吃不完, 买不起
By Michael McGettrick and Wee Khang LinUpdated 12 October 2026
Put (de) or (bu) between a verb and its result and the sentence says whether the result can be reached: (kàn de jiàn), can see; (kàn bu jiàn), can't see. There is no (néng) and no extra verb. It grows straight out of resultative complements.
Quick check
Three quick questions on what you have just read. The full practice is further down.
Pick the right one
0/3得 (can) or 不 (can't)? The English says which.
太远了，我看见。 (It's too far: I can't see it.)
tài yuǎn le ， wǒ kàn ___ jiàn 。 (It's too far: I can't see it.)
别担心，我们吃完。 (Don't worry: we can finish it.)
bié dān xīn ， wǒ men chī ___ wán 。 (Don't worry: we can finish it.)
你说话太快了，我听懂。 (You speak too fast: I can't understand.)
nǐ shuō huà tài kuài le ， wǒ tīng ___ dǒng 。 (You speak too fast: I can't understand.)
The whole system on one screen
The colours stay the same all page long:
| Hanzi | Pinyin | English |
|---|---|---|
| kàn bu jiàn | can't see |
| tīng bu dǒng | can't understand |
| chī bu wán | can't finish (eating) |
| zhǎo bu dào | can't find |
| jìn bu qù | can't get in |
| tīng de dǒng | can understand |
Swap (bu) for (de) and any of them turns positive: (zhǎo de dào), can find. Both middle words are said light, with no tone. The result can be a direction too, as in (jìn bu qù).
The 不 (bu) form does most of the work
You will hear the (bu) form far more often than the (de) one, because people mostly mention a result when it is out of reach:
| Hanzi | Pinyin | English |
|---|---|---|
，。 | Zhème duō cài, wǒmen chī bu wán. | So much food: we can't finish it |
，。 | Tài yuǎn le, wǒ kàn bu jiàn. | It's too far, I can't see it |
，。 | Nǐ shuōhuà tài kuài le, wǒ tīng bu dǒng. | You speak too fast, I can't understand |
。 | Wǒ zhǎo bu dào wǒ de shǒujī. | I can't find my phone |
The object goes after the whole form, as in the last row. The (de) form is just as correct, and turns up mostly in answers and reassurance:
，。- Don't worry, we can finish it.，。- The characters are big, I can see them.
Asking: 吗 (ma), or both forms
Ask with (ma) on the (de) form, or put both forms side by side, as in (qù bu qù):
| Hanzi | Pinyin | English |
|---|---|---|
？ | Nǐ tīng de dǒng ma? | Can you understand? |
？ | Nǐ tīng de dǒng tīng bu dǒng? | Can you understand or not? |
？ | Nǐ kàn de jiàn ma? | Can you see it? |
The answer is the form itself: (tīng de dǒng), yes; (tīng bu dǒng), no. ？ (nǐ tīngdǒng le ma?) asks something else: did you understand, just now?
Can't or didn't: 不 (bu) or 没 (méi)?
(méi) reports what happened. The (bu) form says what is possible:
| Hanzi | Pinyin | English |
|---|---|---|
。 | Wǒ méi tīngdǒng. | I didn't understand (that time) |
。 | Wǒ tīng bu dǒng. | I can't understand (it's beyond me) |
。 | Wǒ méi kànjiàn tā. | I didn't see him |
。 | Wǒ kàn bu jiàn tā. | I can't see him |
The two do not mix: is wrong. Pick (méi tīngdǒng) for didn't, (tīng bu dǒng) for can't.
The potential complement or 能 (néng)?
Both say "can". The potential complement is about whether the action can reach its result. (bù néng) is mostly about something outside stopping you: a rule, a plan, the situation.
| Hanzi | Pinyin | English |
|---|---|---|
，。 | Mén tài xiǎo, wǒmen jìn bu qù. | The door's too small, we can't get in |
。 | Nǐ bù néng jìnqù. | You can't go in (not allowed) |
。 | Wǒ tīng bu dǒng. | I can't understand |
。 | Wǒ míngtiān bù néng lái. | I can't come tomorrow |
For a result out of reach, say (wǒ tīng bu dǒng), not . In the positive both are everyday Mandarin: (wǒ néng tīngdǒng) and (wǒ tīng de dǒng) both mean I can understand.
Not the 得 (de) of 跑得很快 (pǎo de hěn kuài)
The same (de) also says how an action is done, the manner complement on complements. Look at what follows it: a result word means can; a description means how.
| Hanzi | Pinyin | English |
|---|---|---|
。 | Tā pǎo de hěn kuài. | He runs fast (how) |
。 | Wǒ hái pǎo de dòng. | I can still run (not too tired) |
。 | Tā pǎo de bú kuài. | He doesn't run fast |
。 | Wǒ pǎo bu dòng le. | I can't run any more |
The negatives give it away. The manner form keeps (de) and puts (bù) on the description: (pǎo de bú kuài). The potential form swaps (de) for (bu): (pǎo bu dòng).
买不起 (mǎi bu qǐ), 受不了 (shòu bu liǎo): results with their own meaning
A few result words live mostly in the potential form, each with a meaning of its own. (qǐ) is bearing the cost, (liǎo, not le) is managing it at all, (dòng) is moving it, (jí) is getting there in time:
| Hanzi | Pinyin | English |
|---|---|---|
| mǎi bu qǐ | can't afford (to buy) |
| zhù bu qǐ | can't afford to live (there) |
| shòu bu liǎo | can't stand it |
| chī bu liǎo | can't eat (any more, or at all) |
| ná bu dòng | can't carry (too heavy) |
| lái bu jí | not enough time |
| lái de jí | still time |
In sentences:
| Hanzi | Pinyin | English |
|---|---|---|
，。 | Zhège fángzi tài guì le, wǒ mǎi bu qǐ. | This house is too dear, I can't afford it |
，。 | Zhème rè, wǒ shòu bu liǎo. | It's so hot, I can't stand it |
。 | Wǒ chī bu liǎo là de. | I can't eat spicy food |
，！ | Kuài zǒu ba, yào lái bu jí le! | Hurry, we'll be late! |
，。 | Xíngli tài zhòng, wǒ ná bu dòng. | The bags are too heavy, I can't carry them |
Set phrases: 看不起 (kàn bu qǐ) and 怪不得 (guàibude)
Two forms have set into words of their own. Learn them whole:
| Hanzi | Pinyin | English |
|---|---|---|
。 | Tā kàn bu qǐ wǒ. | He looks down on me |
，。 | Guàibude tā méi lái, tā bìng le. | No wonder he didn't come: he's ill |
(kàn bu qǐ) is not "can't see": that is (kàn bu jiàn). (guàibude) has no (de) twin in this sense; treat it as one word.
Mistakes English speakers make
| Wrong | Right | Why |
|---|---|---|
。 | 。 | (méi) and the potential form don't mix; can't is (tīng bu dǒng) |
。 | 。 | (bu) replaces (de) |
。 | 。 | for "he looks down on me": (kàn bu jiàn) is can't see |
。 | ，。 | (bǎ) does not normally take the potential form |
What to do next
- Do the drill below.
- Say three things you can't do, with the
(bu) form:… (wǒ tīng bu dǒng…),… (wǒ mǎi bu qǐ…). - Then read 着 (zhe), the next grammar in the course.