Mars - Neptune (big)
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The Mekong river - The Lena river (long)
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The Amazon rainforest - The Sahara desert (dry)
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The Sahara desert - the Mauna Loa volcano (hot)
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Mars - Earth (warm)
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The Caspian sea - lake Michigan (huge)
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Jupiter - Uranus (freezing)
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The Great Barrier Reef - the Mauna Loa volcano (beautiful)
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K2 mountain - Mount Everest (high)
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Cambodia - Laos (small)
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The Gobi desert - The Somali desert (big)
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The Arctic - the Sahara desert (beautiful)
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