Directivity index
[電] 擇向性指數(shù)
?? 詞語組成解析
[計] 指向性, 方向性
index
['?nd?ks]
n. 索引;<數(shù)>指數(shù);指示;標志;
vt. 給…編索引;把…編入索引;[經(jīng)濟學]按生活指數(shù)調整（工資、價格等）;
vi. [機械學]轉位;
in(in)+dex(proclaim)→指針；索引；指數(shù)；食指；指標
??? 情景例句
What number do I dial?
我應該撥哪個號碼呢？
I have a slight fever.
我輕微發(fā)燒。
If anyone ever asks her how old she is, she always answers, 'Darling, it must be terrible to be grown up!'
“親愛的，長成大人真可怕啊！”