乃[nǎi] 基本解释：
新英汉大词典：
- 乃 (迺、廼)[nǎi]
- 动词- （是; 就是; 实在是） be; be really; be indeed:
Failure is the mother of success.失败乃成功之母。
- 副词- （于是） so; therefore; hence:
It was a steep climb, so we rested for a while halfway up the hill.因山势高峻，乃在山腰休息片时。
- （才） only then:I didn't know it until now.今乃知之。
You can make progress only if you are modest.惟虚心乃能进步。
- 代词- （你; 你的） you; your:
your father乃父
以上内容来源于：《新汉英大辞典》
例句与用法：
There will be an Egyptian mummy show in that country.
Since then, organic materials ranging from Egyptian mummy hair to Stone Age sandals have been dated.
The cultivation of a hobby and new forms of interest is therefore a policy of first importance to a public man.
If he easily pardons, and remits offences, it shows that his mind is planted above injuries; so that he cannot be shot.
Future buildings, roads, and cities may be made from garbage. But so far it is only dream.
乃的其他解释: