It's says find the mid-point and split the list in half. Copy of the back end, sorry, copy of the left side, copy of the right side.

找到列表的中间节点，然后在这里将列表分解成两半，后端的拷贝，左部分的拷贝，右部分的拷贝。

youdao

Facial width-to-height ratio (WHR) is determined by measuring the distance between the right and left cheeks and the distance from the upper lip to the mid-brow.

脸部的宽高比(WHR)是通过测量左右脸颊之间的距离和上嘴唇到眉中的距离得出的。

youdao

Fielding at mid-on to the right-handed Kieswetter, and mid-off to the left-handed Michael Lumb, he proceeded to drop three catches in the first five overs, only one of which was at all difficult.

BBC: Kevin Pietersen fires England to Super Eights victory

Mayweather is the best counter puncher of his era and every time Guerrero missed with a shot, Mayweather would make him pay with a whipping right hand that by mid-fight sliced open Guerrero's left eye.

WSJ: Undefeated Mayweather Returns With Victory