1. 下陷：目前比较广泛是应用在地层下陷(subsidence)的问题里面. 沿海地区养殖所需,会抽取地下水,当饱和土体中的水被抽出来之后,受到有效应力(effective stress)的影响,土体会被压缩. OK!我知道这太专业了,咱们换句话说. 当气球中的水放掉之后,

2. 下沉：subroutine 子程序 | subsidence 下沉 | subsonic reaction 亚音速反应

3. 地陷：subsection 小分段;分区 | subsidence 地陷 | subsidized housing 资助房屋

4. 沉下：subroutine 子程序 | subsidence 沉下 | subsonic 亚声速的

1. 下沉;沉降;下陷
When there is subsidence in a place, the ground there sinks to a lower level.

e.g. A surveyor said that the problems were caused by subsidence and the house needed to be underpinned.
一名勘测员说是地面下陷导致了这些问题出现，房子需要加固地基。

noun

1. the sudden collapse of something into a hollow beneath it

Synonym: cave in

2. a gradual sinking to a lower level

Synonym: settlingsubsiding

3. an abatement in intensity or degree (as in the manifestations of a disease)

e.g. his cancer is in remission

Synonym: remissionremittal