The central structure of the principal piece is axoneme.

主段的中心结构是轴丝。

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The principal chess piece, which can move one square in any direction and must be protected against checkmate.

王象棋中主要的棋子，可以向任何方向移动一个方格，但必须保护它不被将死。

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The surface roughness in mill machining relates to quiver of work piece, principal axis's eccentricity, cutter abrasion, cutter distortion and other physical or geometry factors.

铣削加工表面粗糙度的形成与铣刀和工件振动、主轴偏心、刀具磨损、刀具变形等物理和几何因素有关。

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"Each time you take a piece off of principal, that is a taxable transaction, " Bowers said.

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At the time, people were unfamiliar with the concept of a computer password, which required structuring a scene early in the film in which the main character, played by Matthew Broderick, sneaks into his high-school principal's office to check out a piece of paper showing a list of random words.

WSJ: "Disconnect": From Talkies to Texties

What their corporation did was acquire another piece of real estate that they used as their principal residence.

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