(of a doctor) to say what medical treatment someone should have

The drug is often prescribed for ulcers. 这种药通常是开来治疗溃疡的。

[ + two objects ] I've been prescribed painkillers. 医生给我开了些止痛药。

to tell someone what they must have or do, or to make a rule of something

Penalties for not paying taxes are prescribed by law. 法律上规定了不交税的惩罚措施。

[ + that ] The law prescribes that all children must go to school. 法律规定所有孩子必须上学。

[ + question word ] Grammatical rules prescribe how words may be used together. 语法规则对单词如何搭配使用作出了规定。