それぞれの表現を、例文で見てみましょう！
eg: Are you two-timing me?!
「（私以外のだれかと）二股かけてるの？」
eg: He's a two-timing bastard.
「彼って最低の二股野郎なの」
eg: Be careful. He has a reputation for being a two-timer.
「気をつけて。彼は二股するってうわさだから」
また、「浮気をしている」という意味では、cheatという表現がよく使われます。
eg: Are you cheating on me?!
「あなた（私以外のだれかと）浮気してるの？」
eg: He's a cheating bastard.
「彼は浮気男なんです」
eg: He has a reputation for being a cheater.
「彼は浮気男だってうわさです」
If someone is dating more than one person and the other person is not aware then it is called 'two timing' or 'cheating'.
If the other two people are aware that the person is dating them then it is called an open relationship.
I hope this helps!
嘘をついて複数の人と付き合うことを two timing または cheating と言います。
しかし、二股をかけられている人たちがその関係を知った上で付き合っているのなら、 open relationship と言います。
参考になればうれしいです！
セインさんもおっしゃっているように、"to cheat on someone" で「浮気する」で、ドラマ・映画・日常会話でよく耳にする表現です。
She is cheating on her boyfriend.
あの子は浮気している。
I'm not cheating on you! I promise!
浮気なんかしてないよ！本当に！
Hello Case :-)
I hope this helps
A)He has been two-timing her.
B)She cheated on him.
Sentences A and B are both referring to someone who is not being true to their partner .
Any one of these sentences can be used :-)
Caseさん、こんにちは、参考になるといいです！
A)He has been two-timing her.
B)She cheated on him.
Aの文、Bの文は、パートナーを裏切ることをしている人について言っています。
どちらの表現も使えます。
To have a romantic relationship with two people at the same time.
----------------------------------------
Examples :
James was two-timing her, she left him.
Sam wouldn’t two-time May. He just wouldn’t!
You returned my love with cheating and lies.
She keeps accusing me of cheating when she gets this way.
同時に、別の二人と恋愛関係を持つこと。
例文：
James was two-timing her, she left him.
Sam wouldn’t two-time May. He just wouldn’t!
You returned my love with cheating and lies.
She keeps accusing me of cheating when she gets this way.
①ジェイムスは二股掛けていた、彼女は彼と別れた。
②サムがメイ以外の女性と付き合うなんて絶対にしないよ！
③あなたは私の愛情を浮気と嘘で返した。
④彼女がこういう風になるときは、僕が浮気しているんじゃないかと疑ってかかる。
To 'two-time' someone means to be unfaithful to him/her.
Example
A: Why aren't Jane and John together anymore?
B: He two-timed her with the neighbor.
__________________________________________________________________________________
Two-timer is a term used to call someone who is known to be unfaithful to his/her spouse.
Example
A: John asked me out on a date.
B: You should be careful.
A: Why?
B: He is a two-timer.
____________________________________________________________________________
Two-timing is a term used to describe someone who cheats or is unfaithful.
Example
A: I dislike John.
B: Why?
A: He is a two-timing idiot.
誰かに'two-time'することは、彼・彼女に不貞行為を行うということを意味します。
Example
A: Why aren't Jane and John together anymore?
なんでジェーンとジョンはもう一緒にいないの？
B: He two-timed her with the neighbor.
彼はご近所さんと二股してたんだ。
__________________________________________________________________________________
Two-timerは彼や彼女の配偶者に対して不貞行為を行っている人を呼ぶのに使われています。
Example
A: John asked me out on a date.
ジョンは私をデートに誘ったわ。
B: You should be careful.
気をつけてね。
A: Why?
なんで？
B: He is a two-timer.
彼は浮気者だから。
____________________________________________________________________________
Two-timingは浮気をした、もしくは不貞行為をした人を意味する単語です。
Example
A: I dislike John.
ジョン嫌い。
B: Why?
なんで？
A: He is a two-timing idiot.
彼は浮気したバカよ。
He/She is being unfaithful to her boyfriend/girlfriend.
He/She is having an affair with another man/woman.
Cheating on, being unfaithful to are the most common ways to express this act, but there are other words such as adultery or infidelity that also mean to have an additional relationship outside of the current one.
Also it is important to note that some people/religions allow and accept such behavior.
bigamy - two relationships/spouses
polygamy - more than two relationships/spouses
「Cheating on」や「 being unfaithful」がこの行為を表現する最も一般的な方法です。
また、不倫や浮気ということもできます。今の関係とは別に他で関係があることを意味します。
これを許される地域や人々がいます。
bigamy（重婚） 2人以上の関係や夫婦
polygamy （一夫多妻）-2人以上の関係や夫婦
Such a person may be labelled a 'two-timer,' and may eventually even gain a reputation for being an unreliable and superficial individual! There is no real reason for people to behave like that but it happens over and over again. This behaviour is known as being 'unfaithful.'
"Where's George?"
"Oh, we split up. He was cheating on me!"
"So sorry to hear that."
"It's OK. I realise now he just wasn't serious with me."
二股をかけている人の事を "two-timer" と呼びます。
浮気を繰り返す事は "unfaithful" という単語でも表現できます。
例文
"Where's George?"
（ジョージはどこですか？）
"Oh, we split up. He was cheating on me!"
（ああ、別れたました。彼は浮気をしていました！）
"So sorry to hear that."
（それは残念ですね。）
"It's OK. I realise now he just wasn't serious with me."
（大丈夫です。彼は真剣じゃなかったと言う事に気付きました。）
Someone who is in a relationship with someone other than his/her boy/girlfriend, they are "cheating" or a "two-timer".
If the girl/boyfriend is aware of this, then it is known as an "open relationship".
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