Ancient Greek had the dual form but it has merged with the plural form in modern Greek.

古希腊语中有双数形式，但在现代希腊语中已同复数形式合并在一起了。

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Aim to establish the path independent integral and its dual form of energy type, and to determine the singularity order of stresses near the crack tip in plane quasicrystals.

目的建立平面准晶中能量型路径守恒积分及其对偶形式，并确定准晶裂纹体裂尖应力奇异性阶数。

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Out next is another Sprint Sanyo clam in the form of the dual-band Power Vision SCP-8400 (pictured right) with Bluetooth, 1.3 megapixel cam, and of course live TV, music downloads, and multiplayer game action.

ENGADGET: Sprint launches IP-830W, SCP-8400 and BlackBerry 8703e with GPS

In addition to the new compact form factor, refinements have been made to the dual-analog stick controller to ensure lightning-fast response times and the best gaming experience possible.

ENGADGET: Wikipad in miniature: 7-inch gaming tablet to debut in spring for $249, 10.1-inch sees further delay