Verb + 不 + Verb
Reach for this when you want to say 'can't' in a way that's about physical or situational possibility, not permission. Verb + 不 + complement (like 看不见, 听不懂, 回不去) means 'cannot V because the situation won't allow it.' This is the negative potential complement — extremely common in everyday speech for things like 'I can't see it,' 'I can't go back,' 'I can't understand.' The positive version is Verb + 得 + complement.
Structure
[VERB] 不 [RESULT/DIRECTION]
... bu ...
How to Think About It
Think of 不 as a wedge jammed between the verb and its result. 看见 means 'see' (look + perceive); 看不见 jams 不 in to break the link — you look but perception doesn't happen. Same logic: 回去 → 回不去 (can't manage to go back), 听懂 → 听不懂 (can't manage to understand). The whole structure is one psychological unit: 'try the action, can't reach the result.' It is not the same as 不能 ('not allowed to') or 不会 ('don't know how to').
Examples
我听不懂他说什么。
Wǒ tīng bu dǒng tā shuō shénme.
I can't understand what he's saying.
他们回不去了。
Tāmen huí bu qù le.
They can't go back.
字太小，我看不见。
Zì tài xiǎo, wǒ kàn bu jiàn.
The text is too small, I can't see it.
Common Mistake
Learners often default to 不能 + Verb when they mean 'can't,' even for physical impossibility. 不能 is about permission or external blocking; Verb + 不 + complement is about the result not landing. Saying 我不能听懂 sounds like 'I'm not allowed to understand,' which is nonsense.
我不能听懂中文。
我听不懂中文。
Don't Confuse With
不能 + Verb
'Not allowed to / unable due to rules.' Use 不能 when there's an external block (rule, lack of permission, broken phone). Use Verb 不 Verb when the action just doesn't produce the result.
不会 + Verb
'Don't know how to.' Use 不会 for learned skills you haven't acquired (不会游泳 — can't swim). Use Verb 不 Verb when the skill is there but the situation blocks the result.
Verb + 得 + complement
The positive twin — 'can V successfully.' 看得见 (can see), 听得懂 (can understand). Flip 不 to 得 to express success instead of failure.
Practice
这个字太小，我看___见。
Show answer
不
他说得太快，我听不___。
Show answer
懂
Put in order: [回 / 我 / 今天 / 不去 / 家]
Show answer
我今天回不去家。
Translate to Chinese: 'I can't eat any more.'
Show answer
我吃不下了。
Write a sentence about something you can't do right now, using Verb + 不 + complement.
Show answer
Example: 这本书太难了，我看不懂。 (This book is too hard, I can't understand it.)
Hear It in Real Episodes
This pattern appears in 1 Fluentide episode: