美 [neɪl daʊn]
确保（胜利）：确保某事发生，特指确保胜利或成功。
确定（事实或信息）：准确找出或确认某事物的事实或信息。
确定（决定或计划）：使某事物变得明确或最终确定。
nail down // [ nailing nailed nails ]
动词词组 If you nail down something unknown or uncertain, you find out exactly what it is. 弄清
It would be useful if you could nail down the source of this tension.
如果你能弄清这种紧张情绪的根源，会是有用的。
动词词组 If you nail down an agreement, you manage to reach a firm agreement with a definite result. 确定 (协议)
The Secretary of State and his Russian counterpart met to try to nail down the elusive accord.
美国国务卿与俄罗斯外交部长会晤，试图确定这项表述模糊的协议。
... tagging n. (拉拔前管材端头的)锻尖,(棒材或钢丝端头的)轧尖,磨尖 nail down 确定，明确；用钉钉住 nail someone down: 敲定 ...
... make both ends meet 收支平衡 nail down 达成协议，做成生意 another nail in your coffin 有害健康，危及生命的东西 coffin nail 香烟 ...
... tagging n. (拉拔前管材端头的)锻尖,(棒材或钢丝端头的)轧尖,磨尖 nail down 确定，明确；用钉钉住 nail someone down: 敲定 ...
... wrap up掩饰 nail down用钉子钉住 finalise使结束，使完结...
The Secretary of State and his Russian counterpart met to try to nail down the elusive accord.
美国国务卿与俄罗斯外交部长会晤，试图确定这项表述模糊的协议。
All the parties seem anxious to nail down a ceasefire.
各方面似乎都渴望将停火之事敲定。
It would be useful if you could nail down the source of this tension.
如果你能弄清这种紧张情绪的根源，会是有用的。
It seems wiser policy to think beyond a money hammer to nail down the Suh.
Not a fair question, because Boxleitner had four more seasons to nail down his character.
Back at Sotheby's, I did nail down a glowing Hans Hoffman canvas from 1952.