During the daytime, the sun heats the surface and bubbles of air form and rise into the sky, like the bubbles on the bottom of a pan of boiling water.

白天，太阳将地表加热，空气团上升到天空中，如同一锅沸水锅底的气泡。

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Heat a frying pan or wok on medium-high heat and add 2 tablespoons oil, swirling so that the bottom of the pan is coated.

预热平底锅的中间部分并加上2勺子油，旋转平底锅以致其底被有覆盖。

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Oil the metal cups in the popover pan and place a tiny bit of butter in the bottom of each cup from the bits you cut up.

给泡芙烤盘的金属杯涂点油，在每只杯底放一小点你刚才切好的黄油块。

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Generously cover the bottom of a large frying pan with olive oil and place over a high heat.

CNN: Frankie's parmigiana

Run a thin-bladed knife between the cake and the bottom of the pan to release it, and invert onto a cooling rack.

NPR: Two Centuries of 'Baking in America'

It took two years, 284 pounds of flour and all the ingenuity of her husband, Paul, who lined her stove with quarry tiles and, to produce the necessary burst of steam, dropped a brick into a pan of hot water at the bottom of the oven.

ECONOMIST: Julia Child, cookery teacher, died on August 13th, aged 91