In linguistics, center embedding refers to the process of embedding a phrase in the middle of another phrase of the same type. This often leads to difficulty with parsing which would be difficult to explain on grammatical grounds alone. The most frequently used example involves embedding a relative clause inside another one as in: A man that a woman loves A man that a woman that a child knows loves A man that a woman that a child that a bird saw knows loves A man that a woman that a child that a bird that I heard saw knows loves In theories of natural language parsing, the difficulty with multiple...