They are supposed to be cloaked, so that humans can look right at them and not SEE them, but mistakes are made in the rush to place the boxes, on occasion, so some are left visible.
它们应该是伪装好的，人类就算直直看过去也应该是什么都看不到的，但是在匆忙放置这些盒子的过程中，偶尔出了些差错，导致某些可以被看到。
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