英语词汇optional extra怎么读，是什么意思，单词翻译、读音、固定搭配用法和短语词组及例句-英汉双解词典

单词	optional extra
释义	optional — 任择 adj • 选配 adj • 可选的 adj • 选购 adj • 自选 extra — 余 • 外加 • 零 option n — 方案 n • 选择 n • 选择权 n • 可选择的事物 n • 选修课 n • 购买权 n option — 选择 • 期权 extra adj — 额外的 adj
随便看	release as well release a system release a title release a trigger release authorization release battery release battery pack release bearings release book release bracket release breath release build release button release cable release candidate release capabilities release capacities release carbon release carbon dioxide release carrier release center release Chairman release characteristics release chemicals release chemical substances

英汉双解词典包含2273206条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。

optional —