rule

n.

1. 规则，规定，章程，条例[C]
   It's against the rules of the school to smoke.

   吸烟是违反校规的。

2. 习惯，通例，常规[C]
   He's made it a rule to rise early.

   他已养成早起的习惯。

3. 支配，统治；统治期间[U]
4. 尺；标准[C]