第三者に対して話している時は
father-in-law (義父)
mother-in-law (義母)
ですが、直接[呼ぶ](https://eikaiwa.dmm.com/uknow/questions/75175/)となると欧米ではファーストネームで呼び合うのが一般的だと思います。
例：
She is my mother-in-law.
彼女は私の義母です。
brother-in-law, sister-in-law の場合も同じですね。
例：
My brother-in-law is coming to town.
私の義兄が町に来ます。
他の人に言う場合はfather in law, mother in lawと言いますがAiさんが仰るように外国では義理の[親](https://eikaiwa.dmm.com/uknow/questions/52568/)の名前を[呼ぶ](https://eikaiwa.dmm.com/uknow/questions/75175/)のが一般的です。
For your husband or wife's parents: mother-in-law, father-in-law and in-laws (for both parents).
If it is your boyfriend or girlfriend, you simply call them your boyfriend/girlfriend/partner's parent.
>When married - father in law
>When married - Mother in law
>Not married - Mr. or Mrs
*When you are married to you lover then her/his parents becomes yours and then you can call them "mom" or "dad". But if you are not married it is best to still call them "Mr. %$#" or "Mrs. @#$"
When married - father in law
結婚した時-義父
When married - Mother in law
結婚した時-義母
Not married - Mr. or Mrs
結婚いない-MrもしくはMrs
愛する人と結婚して、相手の両親が自分の「父」や「母」になった時に呼ぶ事ができます。
しかし、まだ結婚していないのであれば、「Mr__」や「Mrs__」と呼ぶ方が良いでしょう。
If you are married then the parents of your spouse are known as your 'in-laws.' However if you are merely talking about an unmarried relationship, then there is no direct and recognised word for that connection and so the parents of your partner would just be called, 'your partner's parents.'
In laws- this is a parent of your husband or wife.
For example: "He is spending the holiday with his in laws."
Father in law-This is the father of either the wife or husband.
For example:" His father in law is really welcoming."
Mother in law- This is the mother of either the wife or husband.
For example: "His mother in law is a very good cook."
"In laws"（義理の）
- これはあなたの旦那さんや奥さんのご両親の事を意味します。
【例】
"He is spending the holiday with his in laws."
（彼は休日を彼の義理の両親と過ごします）
"Father in law"（義父）
-これは旦那さん又は奥さんのどちと言う意味です。
【例】
" His father in law is really welcoming."
（彼の義父はとても心地の良い人だ）
"Mother in law"（義母）
-これは旦那さんか奥さんどちらかのお母さんと言う意味になります。
【例】
"His mother in law is a very good cook."
（彼の義母はとてもりょうりが上手です）
When talking about your partner's parents, you can refer to them as your "in laws" or "father/mother-in-law." If you are not married, you should refer to them as "Mr/Mrs (surname)", or "(partner's name's) parents."
When addressing them directly, you should call them "Mr/Mrs (surname)" unless they ask you to call them something different, i.e. their first names or Mom/Dad.
Mother-in-law
Father-in-law
These are the two terms.
Depending on the relationship you have with them you can call them by their first names, however, when you first meet call them Mr. and Mrs ...... unless they say otherwise. I think that is a good rule of thumb.
Mother-in-law（義母）
Father-in-law（義父）
上記のように言えます。
相手との関係によって、ファーストネームで呼ぶこともあります。ただ、初対面のときは、相手の許可がない限り "Mr. and Mrs ......" で呼んだ方がいいです。
これは一つの基準として覚えておくといいと思います。
These are all ways to refer to the parents of your spouse (your husband or wife).
Ex:
-My father in law is really nice.
-meeting my in laws was really nerve wracking.
-I’m going to spend some time with my mother in law.
これらはどれも「配偶者（spouse）の親」を表す言葉です。
例：
-My father in law is really nice.（義理のお父さんはすごくいい方です）
-meeting my in laws was really nerve wracking.（義理の両親に会うときはすごく緊張しました）
-I’m going to spend some time with my mother in law.（義理のお母さんとしばらく一緒に過ごします）
Depending on how close you are with the parents of your lover, you can call them Ma/Mom/Dad.
When you are speaking about them to other people, you can use the last two examples.
"I am having lunch with my girlfriend's folks later on."
"Ma, would you like me to make you some tea before Jenna and I leave for the movies?"
恋人の親とどのくらい親しいかによりますが、"Ma/Mom/Dad"（お母さん／お母さん／お父さん）と言えます。
恋人の親について誰かと話すなら、最後の二つの例が使えます。
"I am having lunch with my girlfriend's folks later on."（この後彼女の両親と昼ご飯を食べます）
"Ma, would you like me to make you some tea before Jenna and I leave for the movies?"
（お母さん、ジェナと映画を見に行く前に、お茶を入れましょうか）
It depends if you are married with your loved one or not. If yes, you should call them farther or mother-in-law. However, if you are just dating, you should refer to them as Mr. and Mrs. In English, there is no specific words need to be used when you talk with them directly. It is okay and considered normal when you use their first names during the conversation with them.
これは恋人と結婚しているかどうかによります。結婚しているなら "farther-in-law"（義父）または "mother-in-law"（義母）と言えますが、付き合っているだけなら "Mr. and Mrs..." がいいでしょう。
直接話すときには、特定の呼び方があるわけではありません。会話では相手のファーストネームを使うことも一般的です。
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