Verb + 不 + Complement
Use this when you want to say someone is unable to complete an action — not because they won't, but because the conditions don't allow it. Insert 不 between the verb and a result/direction complement: 看不懂 'can't understand (despite looking),' 听不见 'can't hear,' 买不到 'can't manage to buy,' 跑不动 'can't keep running.' This is the potential complement structure in its negative form, and it's the standard way to express 'unable to' in everyday Chinese.
Structure
[VERB] 不 [COMPLEMENT]
[VERB] bu [COMPLEMENT]
How to Think About It
This is different from 不能 ('not allowed' / 'lacks ability in general'). Verb + 不 + Complement says 'I'm doing the action, but the result won't happen.' 看不懂 means 'I'm looking at it, but understanding isn't landing.' Pair each verb with a complement that names the would-be result: 见 (perception), 懂 (comprehension), 到 (reaching/obtaining), 动 (movement), 完 (finishing). The positive flip is Verb + 得 + Complement (看得懂 'can understand').
Examples
这个字太小，我看不清楚。
Zhège zì tài xiǎo, wǒ kàn bù qīngchu.
The characters are too small, I can't see them clearly.
外面太吵，我听不见你说话。
Wàimiàn tài chǎo, wǒ tīng bù jiàn nǐ shuōhuà.
It's too noisy outside, I can't hear what you're saying.
这家餐厅很火，周末买不到位子。
Zhè jiā cāntīng hěn huǒ, zhōumò mǎi bù dào wèizi.
This restaurant is popular — you can't get a seat on weekends.
Common Mistake
Learners use 不能 when they should use V不C, because 'can't' in English covers both. 我不能看懂 sounds like 'I'm not allowed to understand' or 'it's impossible by rule.' 看不懂 is what you actually want — 'I tried, it doesn't click.'
这本书我不能看懂。
这本书我看不懂。
Don't Confuse With
不能 + Verb
不能 is permission or general capability ('not allowed' / 'can't do it as a rule'). V不C says the specific attempt won't yield the result.
没 + Verb + Complement
Past-tense 'didn't manage to' — describes a specific past attempt that failed (没看懂 = 'didn't get it that time'). V不C describes ongoing inability.
Verb + 得 + Complement
The positive twin — 'can' do it (看得懂 'can understand'). Same complement, opposite polarity, swap 不 for 得.
Practice
字太小，我看____清楚。
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不
我太累了，跑不____了。
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动
Arrange: 懂 / 这本 / 我 / 不 / 看 / 书
Show answer
这本书我看不懂。
Translate: I can't finish this much food.
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这么多菜我吃不完。
Write one sentence using Verb + 不 + Complement about something you struggle with.
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这部电影没有字幕，我听不懂里面的对话。
Hear It in Real Episodes
This pattern appears in 1 Fluentide episode:
Related Grammar Patterns
Acquire by listening
Hear Verb + 不 + Complement in real Chinese, not in a textbook.
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