And so while you needed expressions for math to work, there was no point in making anything else return a value, because there could not be anything waiting for it.
所以，如果你需要用数学式子计算一个值，那就只有用表达式返回这个值，没有其他语法结构可用，因为否则就无法处理这个值。
It could be for any reason — a network issue, possibly a problem retrieving particular item from the native repository, or anything at all.
异常可能是任意原因造成的——网络问题，可能无法从本机存储库获得特定条目或任何东西。
What would it be like to sit with it, even for a few minutes a day, to wait for an image - anything that you could hold in your mind or write on paper?
如果你哪怕每天只花几分钟，坐在那里，与之相处，等待一副图景——有什么是你可以想象或记下来的吗？
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