作为一条经验法则，当土壤顶部一英寸感觉干燥时，你就该给植物浇水了。

As ___a ___rule ___of ___thumb, you should water the plant when the top inch of soil feels dry.

一条不错的经验法则是，物品越难以替代，人们往往就越珍视它。

A good ___a ___rule ___of ___thumb is that people tend to value things more if they are hard to replace.

校对时，一条有用的经验法则是先休息一下，然后用全新的视角复查你的作品。

When proofreading, a useful ___a ___rule ___of ___thumb is to take a break and then review your work with fresh eyes.