It means that the seeds from the grain are becoming full.

这意味着谷物的种子变得饱满了。

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Full grain Leather uppers.

全粒面皮革鞋面。

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Upper main ingredient:Black full grain leather.

鞋面主要材料：黑色头层全粒面牛皮；

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And Broin at POET felt that this could allow grain-based ethanol to meet as much of the full 36 billion gallon mandate as could be economically feasible given corn prices.

FORBES: Obama: Corn Ethanol Isn't So Bad After All