七星岩在漓江东岸，是桂林最著名的岩洞，分上、中、下三层。 洞内有地下河，地下画廊，以及许多石钟乳、石笋、石柱等。

Qixingyan in the Lijiang River on the east coast, is one of Guilin's most famous caves, divided into upper, middle and lower three floors.

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钙以方解石（碳酸钙）的形式存在于石灰岩、白垩、大理石、白云石、蛋壳、珍珠、珊瑚、钟乳石、石笋和许多海洋动物的壳体中。

In its compounds calcium has valence 2. It occurs in limestone, chalk, marble, dolomite, eggshells, pearls, coral, and many marine shells as calcium carbonate, or calcite;

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钙以方解石（碳酸钙）的形式存在于石灰岩、白垩、大理石、白云石、蛋壳、珍珠、珊瑚、钟乳石、石笋和许多海洋动物的壳体中。

In its compounds calcium has valence 2. It occurs in limestone, chalk, marble, dolomite, eggshells, pearls, coral, and many marine shells as calcium carbonate, or calcite;

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