A two-faced person says one thing to you and the opposite about you when you are not there. They are friendly to your face and unkind behind your back — and the word says you cannot trust them.

A two-faced person兩面的人 to you對你 says one thing說一套，when you are not there你不在的時候 about you講到你 and the opposite又是相反的一套。They他們 to your face當著你的面 are friendly友善，behind your back在你背後 unkind不客氣——and the word says而這個字要說的是 you cannot trust them你不能信任他們。

It is a strong accusation, stronger than 'dishonest', because it is about betraying someone who thought they were a friend. That is why it hurts: the two-faced person is usually someone close, in your office, in your class, in your group of friends.

It is a strong accusation這是很重的指控，than 'dishonest'比 'dishonest' stronger更重，because因為 it is about它說的是 betraying背叛 someone who thought they were a friend一個以為彼此是朋友的人。That is why it hurts這就是它傷人的原因：the two-faced person這個兩面的人 usually通常 is someone close是身邊親近的人，in your office在你的辦公室、in your class你的班上、in your group of friends你的朋友圈裡。

It is informal and always negative; you use it about people, not about ideas or companies, and almost never about yourself.

It is informal這個字不正式 and always negative而且一定是負面的；you use it about people你拿它說人，not about ideas or companies不說想法或公司，and almost never about yourself也幾乎不會說自己。

The image is of a person wearing two faces, one for each audience — an image that goes back a long way, to the Roman god Janus, who was pictured with a face at the front and a face at the back.

The image is這個畫面是 a person一個人 wearing two faces戴著兩張臉，one for each audience一張臉給一種觀眾——an image that goes back a long way這個畫面由來已久，to the Roman god Janus可以一路追到羅馬神 Janus，who他 was pictured被畫成 with a face at the front前面一張臉 and a face at the back、後面一張臉。