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- 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。
- precursor electron 先驱电子
- The transmitter was pulsed by an electron tube. 电子管使发射器产生脉冲波。
- Thefirst telephone was the precursor of modern communications networks. 最早出现的电话是现代通讯网的雏型。
- The precursor or stem cell of a plasma cell. 成浆细胞浆细胞的前体细胞或干细胞
- An electron tube having a cathode and an anode. 电子二极管有一个阳极和一个阴极的电子管
- A precursor cell of a melanocyte or melanophore. 成黑素细胞产生黑素细胞的母体细胞
- Error is often the precursor of what is correct. 错误常常是正确的先导。
- The precursor or stem cell of a plasmacell. 成浆细胞浆细胞的前体细胞或干细胞。
- An originator of a line of descent;a precursor. 前辈家族血脉的开始者；先驱
- An originator of a line of descent; a precursor. 前辈家族血脉的开始者;先驱。
- A severe cold may be the precursor of pneumonia. 重伤风可能是急性肺炎的先兆。
- The number of electron pairs an atom can share with other atoms. 共用电子对数，共价一个原子与其他原子共用的电子的对数
- Lysine is a precursor of certain alkaloids. 赖氨酸是某些生物碱的前体。
- An electron with a negative charge, as contrasted with a positron. 电子带有负电荷，与正电荷相反的电子
- The first ribin us a precursor of spring. 头一只知更鸟是春天的先兆。
- ARJ21 is seen as the precursor to a jumbo jet. ARJ21型飞机被看作是大型喷气式飞机的前身。
- Her precursor as school principal was an eminent educator. 她任校长前是一位卓越的教育家。
- Attempts to split an electron always fail. 企图分裂电子的尝试总是失败的。
- An electron from one of the atom shells is ejected. 电子从原子的某一壳层中被弹射出来。
