18-8-21 词根词缀背单词 【常用前缀-23】ob-, op- 否，非，反”加强

20.   ob-,op-

①     表示“否，非，反”

object =ob + ject → v. 反对

opponent = op + pon + ent → → n. 对手；a. 对立的 

oppose = op + pos + e → → v. 反抗，对立

opposite = op + posit + e → → n. 对立面；a. 对立的

②     表示“加强”

oblige =ob + lig + e →  v. 迫使，束缚

observe =ob + serv + e → → v. 遵守；引申为观察

obtain = ob + tain →→ v. 获得

oppress = op + press →→ vt. 压迫