nine的序数词怎么写

nine的序数词: ninth

It was almost five years ago, may the ninth .
那是将近五年以前，5月9日。

Beethoven 's ninth symphony is a glorious piece of music .
贝多芬的第九交响曲是壮丽的音乐篇章。

In the ninth year we have challenged the cost and constructed the appropriate experience curve .
在第9年，我们提出了成本问题，并设想了一种相应的经验曲线。

At last we were beaten so far to the south that we tossed and tacked to and fro the whole of the ninth day .
终于，我们被风浪冲击得向南方飘去，在第九天，整整一天，船只忽前忽后地颠簸不停。