卡累利阿桦木蛋是唯一一个使用有机物质(木材)作为主要元素。

However, the Karelian Birch egg was the only one to use an organic substance (wood) as a primary construction element.

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我公司生产的所有玩具均采用优质木材，常用的包括有：榉木、橡胶木、桦木、椴木、松木、MDF、夹板等。

I produced all the toys are of high quality timber, commonly used include: beech, rubber wood, birch, basswood, pine, MDF, plywood and so on.

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