Unobservable
a. 難以察覺的；注意不到的；不可見的
? 同義詞
??? 情景例句
He has had various experiences in his life.
他的生活經驗豐富。
Books,like friends,should be few and well chosen.
書籍如朋友，宜少宜精選。
For them this is a major operation which involves considerable planning.
看戲在他們是件大事，需要精心計劃。