点击下方单词,选择对的这个单词
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1. 钟乳石A stalactite is a long piece of rock which hangs down from the roof of a cave. Stalactites are formed by the slow dropping of water containing the mineral lime.
1. a cylinder of calcium carbonate hanging from the roof of a limestone cave
多通过句子记忆单词，而不是单独死记硬背。
