There are strategies and rules and certain limitations.

VOA: special.2010.04.23

And articles, they're tough because there are certain rules.

冠词难是因为它有一定的规则。

韩国人经常犯的失误 - SpeakingMax英语口语达人

Then there are certain holy days: and they are separated and demarcated from common time by special rules that mark them as different.

然后是一些神圣日：,和普通的时间,被一些特殊的判定它们不同的规则所区分开。

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