The letters "DM" which follow some of the illustrations in the text are an abbreviation for "double movement" and indicate that the movement shown by the arrow (s) is to be made twice.

这两个字母是“两次运动的”的缩写，表示箭头所指示的动作要做两次，这种标法在本文的下面几个章节的展示中还会出现。

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The Preschool Gym is a double story height space that accentuates its scale proportionally to the child's size, promoting the freedom of movement and the physical stimuli of the youngest students.

幼儿园体育场是一个适合儿童身高规模的两层高的空间，为促进幼儿的自由运动和身体刺激。

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A more interesting passage and movement created within and throughout the house with the winding staircase and the many narrow, sometimes wide, double and triple volume Spaces.

在整个住宅中通过螺旋楼梯，以及时而狭窄、时而两到三倍宽的变化的空间体量，使得整个住宅空间既有趣又富有动感。

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Wasps wrapped up victory three minutes from time when Rees bundled over - with the hint of a double movement - and Cipriani added the extras.

BBC: Edinburgh 16-25 Wasps

Leeds should have opened the scoring but the first in a series of crucial errors denied them as Danny McGuire was judged to have made a double movement over the line.

BBC: Hull KR 25-6 Leeds

Depressing a pusher at 8 o'clock initiates a double retrograde movement designed by La Fabrique du Temps.

WSJ: The Feminine Mystique of Watches