英语词汇optional envelope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 envelope
释义	optional — 任择 adj • 可选的 adj • 选配 adj • 选购 adj • 自选 envelope — 信封 • 外壳 • 函 • 封皮 • 焘 envelope n — 封套 n • 包络 n option n — 方案 n • 选择 n • 选择权 n • 购买权 n • 可选择的事物 n • 选修课 n option — 选择 • 期权
随便看	advanced strategies advanced strength advanced structure advanced student advanced studies advanced studies programme Advanced Studies programme advanced style advanced subsidiary advanced supplier advanced support advanced surface movement guidance advanced surfaces advanced surgery advanced suspension advanced sustainability advanced sustainable advanced system advanced system design Advanced tab advanced tab advanced tagging advanced targeting advanced targeting technologies advanced tasks

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 —