Noun:

1. a substance from which another substance is formed (especially by a metabolic reaction)

2. a person who goes before or announces the coming of another

3. something that precedes and indicates the approach of something or someone

ancestorn.祖宗；祖先；原种

antecedentn.前情；先行词；祖先adj.在 ... 之前的；居先的

forerunnern.先驱；祖先；预兆；[体育]赛前试滑滑道的人

predecessorn.祖先；前任；原有事物

heraldn.使者；传令官；先驱；预兆vt.预报；标志

pioneern.先锋；开拓者；先驱v.开辟；首倡

originaladj.原始的；最初的；有独创性的；原版的n.原版；真品；怪人；有独创性的人n.起源

originatorn.创始人；发起人

parentn.父母；根源v.抚养；产生

signn.手势；招牌；符号；迹象；正负号v.签；签名；做手势；做标记

foundationn.根基；基础；根据；创建；基金(会)

leadern.领袖；领导者；指挥者；领先的人

foretasten.预示；预尝v.先尝；试吃；先试

harbingern.先驱；预兆v.预示；作先驱

1. The precursor of the modern car was a horseless carriage with a petrol engine.
   现代汽车的前身是不用马拉的，装有汽油发动机的车子。
2. Her precursor as school principal was an eminent educator.
   她任校长前是一位卓越的教育家。
3. Opposition by colonists to unfair taxation by the British was a precursor of the Revolution.
   殖民地居民对英国不公正税收的反抗预示着革命的到来。
4. Lysine is a precursor of certain alkaloids.
   赖氨酸是某些生物碱的前体。