drop shaft sinking method by multiple caisson

例句：

1. 1. The engineer used the drop shaft sinking method to excavate the tunnel.
   工程师使用多沉井法来挖掘隧道。
2. 2. The construction team adopted the drop shaftsinking method to ensure the stability ofthe foundation.
   施工队采用了多沉井法，以确保地基的稳定性。
3. 3. Thedrop shaft sinking methodwas a revolutionary innovation in engineeringtechnology.
   多沉井法是工程技术领域的一项革命性创新。