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If you want to see how rain comes from the salty ocean (海水) , you can make the water cycle（水循环） happen in a bowl! You need a deep glass ovenware（耐热的） bowl about 25 centimeters （厘米） across, a glass tumbler （大玻璃杯） and some thin polythene （聚乙烯） sheet “cling-film” (塑胶粘膜) . You will also need a spoonful （一勺） of salt and some green or blue food dye （染料） to make “sea water”.
Put some really hot—but not boiling—water into the bowl. There should be enough water so that the tumbler will just stand on the bottom of the bowl without floating （漂浮） . Stir（搅拌） in the salt plus a few drops of dye and stand the tumbler the right way up in the middle of the bowl. Now you have an island surrounded by sea (above right).
Stretch（展开） a layer （层） of cling-film（粘膜） over the top of the bowl and smooth it down the sides so that the bowl is sealed （密封） . Next, squeeze a little air out by pressing down gently （轻轻地） on the film while raising a corner of it for a moment to let out the air. This should produce a dish shaped cover over the bowl which, from underneath （底下） , is like a bulging （凸起） cloud over the island. All you have to do now is to wait and watch.
Water is evaporating （蒸发） from the warm “sea”. When the vapor （蒸汽） reaches the cool cling-film, it condensed on it as tiny drops. These slowly get bigger until they join together forming a drip, which falls into the tumbler. Rain is falling on the “island”! When the rain is dropping steadily, try pouring some ice-cold water on top of the film and watch what happens. Raindrops (雨滴) should form more quickly. You can see that the rain is not colored with the dye and later you can check by lasting the water in the rain with fresh water, not salty.
如果你想了解雨是怎样从海水变来的，你可以在碗里实现它！你需要一只直径大约25厘米的深口耐热玻璃碗，一只平底玻璃杯和一些塑料胶粘膜。你还需要一勺盐和一些绿色或蓝色食用染料来制造“海水”。
将一些确实很烫但没有烧开的水倒入碗中。需要足够多的水以便让杯子刚好立在碗底而不漂浮。把盐和几滴染料搅到水中并把杯子正着放在碗中央。你现在有了一个被海水包围的岛。
在碗顶部罩一层粘膜并顺碗边向下把碗密封起来。接下来，通过轻轻按下薄膜的一角等待片刻，以赶出一点空气。这样做出盖在碗上的一个盘状盖子，从底下看，像岛上空凸起的云。剩下要做的就是等待和观察了。
水从温暖的“海”里蒸发。当蒸汽遇到冷的粘膜，就凝结在上面形成小水珠。水珠逐渐变大直到合起来形成一个水滴落入杯中。“岛”上在下雨！当雨水不断滴下，在膜上加一些冰水并观察发生的情况。雨滴应该形成得更快。你可以看到，雨并未被染料上色，随后你可以通过尝试杯子里的水来检验雨是淡水，而不是咸水。
记忆词卡（开通基础词汇）
bowl 碗
boil 沸腾
island 岛
press 压、按
tiny 细小的
squeeze 挤、压榨
Put some really hot—but not boiling—water into the bowl. There should be enough water so that the tumbler will just stand on the bottom of the bowl without floating （漂浮） . Stir（搅拌） in the salt plus a few drops of dye and stand the tumbler the right way up in the middle of the bowl. Now you have an island surrounded by sea (above right).
Stretch（展开） a layer （层） of cling-film（粘膜） over the top of the bowl and smooth it down the sides so that the bowl is sealed （密封） . Next, squeeze a little air out by pressing down gently （轻轻地） on the film while raising a corner of it for a moment to let out the air. This should produce a dish shaped cover over the bowl which, from underneath （底下） , is like a bulging （凸起） cloud over the island. All you have to do now is to wait and watch.
Water is evaporating （蒸发） from the warm “sea”. When the vapor （蒸汽） reaches the cool cling-film, it condensed on it as tiny drops. These slowly get bigger until they join together forming a drip, which falls into the tumbler. Rain is falling on the “island”! When the rain is dropping steadily, try pouring some ice-cold water on top of the film and watch what happens. Raindrops (雨滴) should form more quickly. You can see that the rain is not colored with the dye and later you can check by lasting the water in the rain with fresh water, not salty.
如果你想了解雨是怎样从海水变来的，你可以在碗里实现它！你需要一只直径大约25厘米的深口耐热玻璃碗，一只平底玻璃杯和一些塑料胶粘膜。你还需要一勺盐和一些绿色或蓝色食用染料来制造“海水”。
将一些确实很烫但没有烧开的水倒入碗中。需要足够多的水以便让杯子刚好立在碗底而不漂浮。把盐和几滴染料搅到水中并把杯子正着放在碗中央。你现在有了一个被海水包围的岛。
在碗顶部罩一层粘膜并顺碗边向下把碗密封起来。接下来，通过轻轻按下薄膜的一角等待片刻，以赶出一点空气。这样做出盖在碗上的一个盘状盖子，从底下看，像岛上空凸起的云。剩下要做的就是等待和观察了。
水从温暖的“海”里蒸发。当蒸汽遇到冷的粘膜，就凝结在上面形成小水珠。水珠逐渐变大直到合起来形成一个水滴落入杯中。“岛”上在下雨！当雨水不断滴下，在膜上加一些冰水并观察发生的情况。雨滴应该形成得更快。你可以看到，雨并未被染料上色，随后你可以通过尝试杯子里的水来检验雨是淡水，而不是咸水。
记忆词卡（开通基础词汇）
bowl 碗
boil 沸腾
island 岛
press 压、按
tiny 细小的
squeeze 挤、压榨