Sifting is important for soft, fluffy, and airy biscuits.

想要做出松软、蓬松、有气孔的酥饼，用筛子筛一筛是很重要的。

We must sit without light. He would see it through the ventilator. I nodded again.

我们必须摸黑坐，他会从通气孔发现有亮光的。我头。

Then the kinda-liquid-kinda-gas can drift out of the solid molecular structure, and be replaced by air, so you have a porous, lightweight material that retains its shape.

然后，这种似液体似气体的物质可以从坚固的分子结构中漂移出来，被空气所取代，这样你便得到有气孔的还保持原始形状的极轻材料。