美國ARCO 權威托福參考詞匯：O字頭

O

oath

n.誓言, 宣誓, 詛咒 a solemn attestation of the truth or inviolability of one’s words

obstacle

n.障礙, 妨害物 something that impedes progress or achievement

ominous

adj.預兆的, 惡兆的 being or exhibiting an omen : PORTENTOUS;

on the spot

adv.當場, 在危險中, 處于負責地位

operation

n.運轉, 操作, 實施, 作用, 業務, 工作, 手術 

option

n.選項, 選擇權 the power or right to choose : freedom of choice

outlawe

n.歹徒a lawless person or a fugitive from the law

逃犯 a person excluded from the benefit or protection of the law

v. 宣布...為不合法to deprive of the benefit and protection of law : declare to be an outlaw

overlap

v.(與...)交迭 to extend over or past and cover a part of

overwhelm

vt.淹沒, 覆沒 to cover over completely : SUBMERGE 顛覆，推翻UPSET, OVERTHROW