to fall in
[phrase form: fall]
01
倒塌, 坍塌
to collapse under pressure, often due to structural weakness
例子
The old well, weakened by erosion, finally fell in after a heavy rainstorm.
被侵蚀削弱的旧井，在一场暴雨之后终于倒塌了。
As the earthquake shook the region, several buildings started to fall in, causing widespread damage.
当地震震动该地区时，几座建筑物开始倒塌，造成大范围的破坏。
02
加入, 参加
to join a group or organization
例子
Excited about the cause, he decided to fall in and become an active member of the environmental organization.
对这个事业感到兴奋，他决定加入并成为环保组织的活跃成员。
After attending several meetings, she felt a sense of belonging and chose to fall in with the community group.
参加了几次会议后，她感到了一种归属感，并选择加入社区小组。
03
列队, 就位
to assume one's designated position within a military formation or line, typically prompted by a command or order
例子
When the bugle sounded, the soldiers quickly fell in, ready for the morning drill.
当号角响起时，士兵们迅速列队，准备进行晨练。
As the officer entered the parade ground, the troops fell in with precision.
当军官进入阅兵场时，部队精确地列队。
