Definition
to ensure that something is absolutely certain or confirmed
確定；確保
We need a plan to ensure that the project is completed on time, so we have to nail this idea on.
我們需要一個計劃來確保項目按時完成，所以我們必須確定這個想法。
During the meeting, the manager stressed the need to nail down the objectives so that everyone knows their tasks.
在會議中，經理強調需要確定目標，以便每個人都知道自己的任務。
To avoid any misunderstandings, we should nail down the terms in the contract.
為了避免任何誤解，我們應該確定合約中的條款。