Definition: a time when something happens Level: B2
有一次，老师离开了教室。
On one ___occasion, the teacher left the class.
我们已经在几个场合讨论过这件事了。
We've discussed this matter on a few ___occasions.
我们只在特殊场合才用那套精美的瓷器。
We only use the fancy china for a special ___occasion.
