没发生的英文：
do not happen
do not occur

参考例句：

We can't get unwary just because nothing unusual has cropped up
不能因为没发生什么问题就麻痹大意起来。

Nothing have happened in the interim.
在过渡期间，没发生过任何事。

The kite flew high in the rainy sky, but nothing happened.
风筝在雨天的空中飞得很高，但什么事情也没发生。

Very little happened while J.Q.Adams was President. It was an unhappy time for him, and he wasn't very effective.
小亚当总统在任时期，美国没发生什么重大事件。对他来说，这是一段不愉快的时光，而且他不是一位卓有成效的总统。

happen是什么意思：
v. 偶然遇到；发生；出现；碰巧

These things will happen.
这种事总要发生的。

It happened far back in the past.
这事发生在久远的过去。

A string of accidents happened at that corner.
在那个转角发生了一连串的事故。

Accidents are happening with increasing frequency.
事故发生得越来越频繁。

That happened in the remote past.
那发生在久远的过去。

occur是什么意思：
v. 发生；出现；存在

Something unexpected occurred.
发生了意料之外的事。

Symbiosis occurs in a community.
共生现象出现在群落中。

They expect bonding to occur naturally.
他们希望能够建立自然的关系。

Events of this description occurred daily.
这类事件天天发生。

Change occurs at a glacial pace.
变化极其缓慢。