be familiar with
be very familiar to
know well ?
be acquainted with
familiar 英[fm?li?(r)] 美[fm?lj?] ?adj. 熟悉的; 通曉的; 冒昧的; 隨便的; n. 常客，密友; 高級官吏的家屬; [天主]教皇[主教] 的仆人; [例句]He talked of other cultures as if they were more?familiar?to him than his?own他談起其他文化時似乎比對他自己的文化還要熟悉。
sb be familiar with sth
sth be familiar to sb
familiar to =well known to，意思是為…所熟知的。
familiar with =well acquainted with意思是對…了解的；對…熟悉的。
例句：
familiar to
This person looks quite familiar to me. 這個人面善得很。
English is familiar to me. 英語為我所熟悉。
He looks familiar to me. 他很面善。
The facts are familiar to me. 這些事實對我來說是熟悉的。
familiar with
Most people are familiar with this figure from Wagner's opera. 多數人都熟悉瓦格納歌劇中的這壹人物。
We are very familiar with each other. 我們相互之間很熟。
3、I am not familiar with his character. 我不了解他的性格。
4、I am not very familiar with botanical names. 我不太熟悉植物學方面的名稱。
acquainted 英[kwe?nt?d] 美[kwent?d] adj. 了解; 熟悉; 知曉（某事）; 交遊甚廣的; v. 使熟悉( acquaint的過去式和過去分詞 ); 使了解; 通知; 告知; [例句]He was well?acquainted?with the literature of France, Germany and?Holland他對於法國、德國和荷蘭的文學了如指掌。[其他] 原型：?acquaint