back layer

基本解释

The back layer is more complicated. The main points to notice are
后面的图层就比较复杂了。
The retina is the inside back layer of the eye that records the images a person sees and sends them via the optic nerve from the eye to the brain.
视网膜处于人眼最内层后部，它收集人眼所见同时将视觉信号通过视神经传至大脑。
Next, we select the back layer and apple a Filters >Distort >Wave transform. You may need to fiddle with the settings, as you don’t want to distort it too much.
下一步，我们选择黑色的图层，然后应用滤镜——扭曲——波浪命令，你需要注意这些设置，不要扭曲的太多。

The Maya poured the chocolate drink back and forth between two containers so that the liquid had a layer of bubbles,or foam.
We'll pull back that layer before long.
我们不久后会撤销那一层。
哈佛公开课 - 计算机科学课程节选
And so if we wanted to do this here, it's again, the same thing we're just now pulling back this layer and calling them char *s not actually strings.
如果我们想要在这里这样做，再次，我们撤销这一层,把它们叫做char，*s，实际上不是字符串。
哈佛公开课 - 计算机科学课程节选

Richard Rhodes, in his Pulitzer Prize-winning book, The Making of the Atomic Bomb, peels back, layer by layer, the invention of the atomic bomb.
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