supporting jack

例句：

1. 1. The engineer useda supporting jack to lift the heavymachine onto the platform.
   工程师使用支持式千斤顶将重机器提升到平台上。
2. 2. Theconstruction workers were using a supporting jackto support the roof during the rainyseason.
   建筑工人在雨季使用支持式千斤顶支撑屋顶。
3. 3. The engineer had to usea supporting jack to lift the heavyequipment onto the construction site.
   工程师不得不使用支持式千斤顶将重型设备提升到施工现场。