測量士は水準を用いて土地の高低差を調べた。
The surveyor used a level to check the differences in the land's height.
大工は水準を当てて床が平らかどうか確かめた。
The carpenter held a spirit level against the floor to check that it was flat.
まず水準を定めてから基礎工事に取りかかる。
We first establish the level and then begin the foundation work.