occasion 
英 [əˈkeɪʒən]  美 [əˈkeɪʒən] 
n. 场合，盛典；时机

v. 引起，惹起

例句：
On one occasion, his father took him to the zoo. 

有一次，他父亲带他去了动物园。

He acted as chauffeur on this occasion for Iris. 

在这种情形下，他给艾丽丝当了司机。

a comment made on an earlier occasion 

早些时候说的一句话

I met her on several occasions. 

我见过她几次。

Mr Davis has been asked on a number of occasions. 

戴维斯先生被询问了很多次。