occur sporadically [now and then], happen occasionally
- 相手チームを5安打の散発におさえる
- hold the opposing team to five scattered hits
- 散発的な銃撃が夜じゅう続いた
- Sporadic shooting continued through the night.
- 最近この地域にひったくり事件が散発している
- There have been several scattered cases of bag-snatching in this area recently.