If headaches only occur at night, lack of fresh air and oxygen is often the cause. [VERB]

如果只是在晚上頭疼，那常常是由於缺乏新鮮空氣和氧氣的緣故。

The crash occurred when the crew shut down the wrong engine. [VERB]

機務人員關錯了引擎，随即飛機墜毀。

In March 1770, there occurred what became known as the Boston Massacre.

1770年3月在那裏發生了後來聞名的波士頓慘案。

The cattle disease occurs more or less anywhere in Africa where the fly occurs. [VERB adv./prep.]

在非洲凡是有這種蠅蟲的地方，幾乎都會出現這一牛病。

These snails do not occur on low-lying coral islands or atolls. [VERB adv./prep.]

在地勢低平的珊瑚島或環礁上沒有這種螺。

It did not occur to me to check my insurance policy. [V to n to-inf]

我沒有想到要核實我的保險單條款。

It occurred to me that I could have the book sent to me. [it V to n that]

我想到可以讓人把書寄給我。

The same idea had occurred to Elizabeth. [VERB + to]

伊麗莎白也想到了這個主意。