ph.
1. 弄清;确定
If you nail down something unknown or uncertain, you find out exactly what it is.
2. 确定(协议)
If you nail down an agreement, you manage to reach a firm agreement with a definite result.
3. 钉牢;钉住
If you nail something down, you fix it firmly onto something.
1. make final
put the last touches on
put into final form
e.g. let's finalize the proposal
Synonym: finalizefinalisesettle
2. define clearly
e.g. I cannot narrow down the rules for this game
Synonym: pin downpeg downnarrow downnarrowspecify
3. succeed in obtaining a position
e.g. He nailed down a spot at Harvard