[母国語](https://eikaiwa.dmm.com/uknow/questions/50243/)はfirst language,mother tongueと言います。
「あなたの母国語はタガログ語です」は
Your first language is Tagalog.
となります。
first = [最初の](https://eikaiwa.dmm.com/uknow/questions/70010/)
mother = 母
tongue = 舌（直訳）
first language = 第一言語、母国語
mother tongue = 母国語
参考になれば幸いです。
Mother tongue =the language which a person has grown up speaking from early childhood.
If I was born and raised in the UK, and only speak English, then my mother tongue is English. Possibly it could happen that someone's mother only speaks, for example, Hindi to a child, yet they live in another country but do not mingle with the local population. In that case, the mother tongue would be Hindi.
"What's your mother tongue?"
"English."
Mother tongue =[母国語](https://eikaiwa.dmm.com/uknow/questions/50243/)、子どものころから使っている[言語](https://eikaiwa.dmm.com/uknow/questions/32885/)
ＵＫで生まれて育り英語しか喋らないのなら、私の母国語は英語になります。ひょっとするとお母さんの言葉という意味からしれませんね。もし違う国に住んでいても、お母さんから子供に対してはヒンドィの言葉が喋られ、地元の人間とは交流しなかったら、きっときっと母国語はヒンディになるでしょう。
"What's your mother tongue?" 母国語は何？
"English.英語。
*Mother tongue is a language that a person speaks from childhood.
A: Mum you amaze me, Tagalog is your mother tongue but you speak English fluently.
B: I learnt English as a second language when i was grade 10.
*Mother tongueとは、母国語のことです。
例文
A: Mum you amaze me, Tagalog is your mother tongue but you speak English fluently.
「お母さんってすごいね。タガログ語が母国語なのに、英語がとても上手で。」
B: I learnt English as a second language when i was grade 10.
「私は高校一年生のときから、第二外国語で英語を勉強したのよ。」
Mother tongue' is the language that someone has grown up speaking. It's the first language that you were introduced to.
Example:
Q: What's your mother tongue?
A: English is my mother tongue.
Q: What's your first language?
A: English is my first language and French is my second language.
「mother tongue」は子どもの頃から話してきた言語を言います。
一番初めに習った言語のことです。
例:
Q: What's your mother tongue?（母語は何ですか）
A: English is my mother tongue.（英語が母語です）
Q: What's your first language?（第一言語は何ですか）
A: English is my first language and French is my second language.（英語が第一言語で、フランス語が第二言語です）
If your home language is Tagalog, how come are you this fluent in English?
How are you so fluent in English when your mother tongue is Tagalog?
"If your home language is Tagalog, how come are you this fluent in English?"
- A home language is your native language. It is the language you grew up speaking at home.
In this question you are asking your teacher how come he/she is fluent in English when he/she grew up speaking Tagalog.
"How are you so fluent in English when your mother tongue is Tagalog?"
- The main aim of this question is more about knowing how your teacher is so fluent in English when its not her native language.
"If your home language is Tagalog, how come are you this fluent in English?"
- "home language" とは「母語（native language）」のことです。
子どもの頃家で話した言語ということです。
「母語がタガログ語なのに何でそんなに英語が流ちょうなの？」と尋ねています。
"How are you so fluent in English when your mother tongue is Tagalog?"
-「英語が流ちょうな理由」に焦点を当てた質問です。
「英語が母語ではないのに何でそんなに流ちょうなの？」と尋ねています。
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