Permittivity of free space
[化] 真空电容率; 真空介电常数
🧩 词语组成解析
n. 介电常数, 电容率\\n[化] 电容率; 介电常数
of
[əv]
prep. 关于;属于…的;由…制成;
aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气];
free
[fri]
adj. 自由的;免费的;免税的;空闲的;
adv. 免费地;自由地，无拘束地;一帆风顺地;
vt. 免除;释放;使自由;解救;
space
[spes]
n. 空间，太空;空白，间隔;空隙;片刻;
vt. 把…分隔开，留间隔于…之间;
vi. 以一定间隔排列;
🗣️ 情景例句
Hello. This is a representative of Zhongyou Department Store.
喂，您好。我是中友百货的。
Keeping is harder than winning.
创业不易，守业更难。
'He had travelled only seven miles across the Channel when his engine failed and he was forced to land on sea.
但他只在海峡上空飞行7英里，引擎就发生了故障，他只好降落在海面上。