crop up

突然发生, 突然出现

例句与用法：

Another development related to the electronic cottage is the emergence of electronic "halfway houses" which are beginning to crop up across the country.

与电子业有关的另一项新发展是电子“中间站”的出现，这种中间站正开始在全国各地涌现出来。

A difficulty has cropped up at work.

工作中突然出现困难。