I would say the brain, but the heart is also related because the complex concept of love is formed by both bottom-up and top-down processes from the brain to the heart and vice versa.

我想说是脑，但与心也是有关联的，因为恋爱这个复杂的概念即是自底向上的又是自顶向下的，即是从脑到心的，又是从心到脑的。

youdao

At these two corners they must be double from the bottom all the way to the top, and fitted into a single ring; both shall be like that.

板的下半截要双的，上半截要整的，直顶到第一个环子；两块都要这样做两个拐角。

youdao

Instead, I scan the board from left to right and top to bottom (twice, to get both horizontal and vertical words).

我的方法是，从左到右，从上到下对谜板进行扫描(两遍，这是为了得到垂直方向和水平方向的词)。

youdao

These were both simple products that were fads embraced by our culture from top to bottom and the investing public latched on as well.

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Products coming from the 90s and 2000s have contributed handsomely to both the top and bottom lines over the past 10-20 years.

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Then both (full) flights boarded from the same gate, jamming the entire winding concourse from top to bottom.

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