自然凹陷：地表或地下的自然凹陷，通常由于地质构造或水力作用引起。
A sinkhole is a natural depression caused by the removal of underground soil by water.
阿灰岩坑是一个天然洼地，由地下土壤除水造成的。
In the mood-congruent experiment, disabilities of explicit memory were possibly found in natural depression subjects.
在心境一致性实验中，自然抑郁组被试可能存在外显记忆缺损。
During the Depression, bankers were natural targets of scorn.
在大萧条期间，银行家自然是最受轻蔑的对象。
Seems natural to ascribe depression to Marvin, the robot.
消极"用在机器人身上,似乎再自然不过
死亡课程节选 : 耶鲁公开课
Spengler was firing from "a natural depression" against a bank and a tree, he said.