没有语法错误，how to choose做主语

  有 正确的应该是That how to choose is a kind of knowledge. 或者It is a kind of knowledge that how to choose.

  不能听2楼的,这里的how to choose是疑问不定式做主语,is是谓语.后面的则是表语.整个句子没有语法错误 2楼说的那个that必须是放在完整的句子前面的. That he can't do it is true. It's true that he can't do it.

  哈哈 有意思