The thimble also called chain repitition or reelection, referred to as the beginning word of the following sentence with the last word of the previous sentence, the adjacent clauses won. This is a relatively common couplet, but also very able to reflect the characteristics of Chinese characters.
A thimble is a shell worn by a dressmaker to protect a finger when it is worn by a finger
Refers to the thimble hole in the mold