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]

vt.

1. 统治，管辖；控制，支配
   The queen ruled her country for 20 years.

   女王统治了她的国家二十年。

2. 裁决，裁定[O][+that]
3. （用尺）划（线）

vi.

1. 统治，管辖；控制，支配[（+over）]
   He ruled over the country for ten years.

   他统治这个国家十年。

2. 作出裁决[（+on）]
   The court ruled in her favor.

   法庭判她胜诉。

3. （价格等）维持在某一水平

n.

1. a regulation or principle governing conduct or procedure within a particular area of activity.
   ▸a code of practice and discipline for a religious community:

   the Rule of St Benedict.
2. control or government:
   an end to British rule.
3. (the rule) the normal or customary state of things.
4. a straight strip of rigid material used for measuring; a ruler.
5. a thin printed line or dash.

v.

1. exercise ultimate power over (a people or nation).
   ▸exert a powerful and restricting influence on.
   ▸informal be very good or the best.
2. pronounce authoritatively and legally to be the case.
3. [often as adj. ruled] make parallel lines on (paper).
4. (rule something out/in) exclude (or include) something as a possibility.