These changes have occurred over a long time span.

这些变化经过了很长一段时间才形成。

《牛津词典》

Similar incidents have occurred before.

类似的事件以前也发生过。

youdao

That seems to have occurred first in Central America.

这似乎首先发生在中美洲。

youdao

"The feeling in the community is that many of these deaths have occurred immediately after the recovery agents of the microfinance institutions have either visited the house or have done something insulting."

VOA: special.2010.11.12

There are very important public health victories that have occurred along the way with supplementation of these sort of things.

公共健康领域的一系列重大胜利,就是在食物添加矿物质的历程中取得的

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

None of England's pre-Miltonic poets -- Chaucer, Spenser, Shakespeare had dared to suggest -- and it would never have occurred to them to suggest that theirs was actually a divine vocation.

在弥尔顿之前，包括乔叟，斯潘塞和莎士比亚,没人敢这么说-他们从不敢,说自己的职业是神圣的。

耶鲁公开课 - 弥尔顿课程节选

To cope, the power companies have shut off generators and power outages have occurred.

FORBES: Investing In China Is Fraught With Business Landmines

Moreover, if backdating occurs without the compensation committee's knowledge, illegal insider trading may also have occurred.

FORBES: The Next Big Scandal

Between 82 and 97 casualties are believed to have occurred as a result of these attacks.

CNN: Somali pirates cost global economy '$18 billion a year'