optional什么意思解释？

optional的反义词有：compulsory, required, compulsory。adj.optional的反义词（随意的;选修的）：compulsory。optional的反义词（其他释义）：required, compulsory。...

optional的音标：optional的英式发音音标为：['ɒpʃənl]optional的美式发音音标为：['ɑpʃənl]...

optional的近义词/同义词有：voluntary, elective, voluntary, elective。adj.optional的近义词（自愿的,志愿的）：voluntary, elective。optional的近义词（其他释义）：voluntary, elective。...

We also recommend a full day optional excursion to the Upper Douro.我们还推荐去杜罗河上游的短途自选一日游。The course consists of ten core modules and five optional modules.这门课程包括十个必修单元和五个选修单元。Certain courses are compulsory, others are opti...

Optional extras include cooking tuition at a top restaurant...可选的额外项目包括在顶级餐厅学习厨艺。The goods are optional, but only one.这些物品是可以任选的, 但只能选一个。Elevation view of a tapered key with optional gib head.具有可选钩头的锥形键的正视图.The third col...

exordium的复数形式为：exordiums...

Histidine A basic amino acid formed only rarely in proteins.组氨酸:是蛋白质中少有的一种碱性氨基酸.D - histidine is a necessary acid for man and animal.其中,D - 组氨酸是人体和动物必需的氨基酸.Other: The dyewood is known as the suppression histidine decarbo...

你可以品尝酥油奶茶.You can drink tea laced with milk , butter, and grain.酥油有很高的营养价值.Butter has a high nutritional value.用菜籽油或大豆油替代部分氢化酥油来煎炸鸡肉是个容易的转换.Frying chicken in canola or soybean oil instead of partially hydrogenated shorte...

n.寓言，格言...

Two guards with sidearms patrolled the wall.两名配枪警卫在城墙上巡逻。Soldiers patrolled the castle ramparts.士兵们在城堡城墙上巡逻.Troops patrolled the border day and night.军队日夜在边境地区巡逻。...a barbed-wire fence patrolled by armed guards...有武装警卫巡逻...

“火炉”的英语可以翻译为：stovepipe，(heating) stove，burner，chimney place，furnace ...

n.格子，非实质的，地图上的坐标方格，（输电线路、天然气管道等的）系统网络...

When the heart is afire,some sparks will fly out of the mouth.心里有什么,嘴里总要泄露出来。The clinic was set afire.诊所被人放火了.Sydney is afire with Olympic enthusiasm.悉尼全城燃烧着奥林匹克的热情。When the heart is afire, some sparks will fly out of th...

histamine的音标：histamine的英式发音音标为：['hɪstəmi:n]histamine的美式发音音标为：['hɪstəˌmin, -mɪn]...

“束发”的英语可以翻译为：hairdo ...

他在学校的时候有名地笨嘴拙舌, 现在却变得伶牙俐齿.He was famous for his clumsiness of speech, but now he is quite eloquent....

encamp的音标：encamp的英式发音音标为：[ɪn'kæmp]encamp的美式发音音标为：[ɪn'kæmp]...

n.生物量热法...

The constitution of mediatory acceptance of bribe has always been a problem at issue.斡旋受贿的构成一直是有争议的问题....

纤维光电子学...