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1·The leaves of the compass plant always point north.

叶植物的指南针总是指向北方。

2·Compass plant A plant with its leaf edges permanently aligned due north and south.

一类叶片的边缘始终南北排列的植物。

3·The best - known example is the compass plant of the prairies ( Silphium laciniatum ).

最著名的例子是大草原上的指向植物（ 罗盘草）。

4·The concentration of carbon dioxide in the air being only 0.03 percent; carbon is amassed into the compass of the plant form a large volume of air.

因为空气中二氧化碳的密度只有万分之三，所以聚集在植物内部的碳是从周围极大体积的空气中得来的。