Everyone seemed to know that this was an important occasion.

In those days museum was opened to the public only on important religious occasions.

That is rather a silly question on such an important occasion.

A donation to the church or their chief at an important occasion.

"Such things should only be played on certain important occasions."

As he pointed out, there were two very important occasions to be considered that day.

Then he was made a Prince, and needed a real lady to be by his side on important occasions.

True, she had brought a dress with her, but was it grand enough for such an important occasion?

It is the second time I have found them not here on an important occasion.

Of course, what to wear on these important occasions is no small question.