我不知道你不會游泳。

I didn't know you didn't know how to swim.

Source: Tatoeba

Sentence Composition

1 我不知道 wǒbùzhīdào I don't know.
=2 你 nǐ you (informal, as opposed to courteous 您 nín)
=2 你 nǐ you (Note: In Taiwan, 妳 is used to address females, but in mainland China, it is not commonly used. Instead, 你 is used to address both males and females.)
3 不會 bùhuì
  1. improbable
  2. unlikely
  3. will not (act, happen etc)
  4. not able
  5. not having learned to do sth
  6. (coll.) (Tw) don't mention it
  7. not at all
=4 游泳 yóuyǒng
  1. swimming
  2. to swim
=4 游泳 yóuyǒng misspelling of 游泳 (yóuyǒng)