We're so sorry for speaking only (in) Japanese today.
We want to apologize to you for talking only in Japanese today.
"be so sorry for 〜" は「〜して大変申し訳ないと思う」という意味の表現です。
"speak only (in) Japanese" は「日本語だけを(で)話す」ということを表します。他に "talk in Japanese" や "have a conversation in Japanese" と言うこともできます。
"apologize to 人 for 〜" は「人に〜したことを謝る」という表現になります。
"I'm sorry for...." & "I apologize for..." are phrases that can be used to apologize for something that you did or that someone else thought you have done.
"I'm sorry for...." と "I apologize for..." は、自分がしたことについて、もしくは誰かがあなたがしたと思ったことについて謝るときに使えます。
Sorry that we only spoke in Japanese. I hope you did not feel left out.
When you are part of a group of people who are a different nationality to yourself and they are speaking their native language it can make one feel isolated or left out of the conversation.
If you are one of the group who are speaking then when apologising it is polite to first of all apologise and then explain that you hope they did not feel 'left out' of the conversation. Some people enjoy listening to others speak their native language as this is a good way of learning new phrases or words.
My Swedish friends used to speak Swedish a lot around me and after they had finished their conversation they would often say, "sorry for the Swedish" - but meaning the Swedish language not Swedish people. It's a polite phrase to make you feel not so left out and forgotten!
私のスウェーデンの友達は、私まわりでよくスウェーデン語で話していました。そして会話が終わると、"sorry for the Swedish" 「スウェーデン語でごめんね」と言ったものです。相手が疎外感を感じないように一言伝えるのは丁寧です。
The two sentences provided above are great ways to apologize to someone who did not understand Japanese. In the second sentence you will see the verb gab. This word means to talk or chat. We use this word in our everyday conversation, so it would be appropriate in an informal setting like talking with family or friends.
If you apologise you are saying you are sorry for something so to say "we apologise/are sorry for only talking in Japanese today" that gets the point across to the person easily
"Apologise"（謝る）は、相手に対して申し訳ない気持ちを表す言葉です。
”We apologise／We are sorry for only talking in Japanese today"（今日は日本語だけで話してしまってごめんなさい）と言えば、相手に気持ちが伝わる筈です。
I'm sorry, I don't understand Taiwanese. I;m sorry for only speaking Japanese to you
I don't speak Taiwanese, that why I speaking Japanese to you all the time.
I'm sorry we only spoke in Japanese
When you want to apologize to your Taiwanese friends that you only spoke Japanese in your conversation with them; then you can say:
-I'm sorry, I don't understand Taiwanese. I;m sorry for only speaking Japanese to you
-I don't speak Taiwanese, that's why I speak Japanese to you all the time.
-I'm sorry we only spoke in Japanese
台湾人の友達に日本語でばかり会話をしていたことを謝りたいなら、次のように言うことが出来ます：
【例文】
-I'm sorry, I don't understand Taiwanese. I'm sorry for only speaking Japanese to you
（台湾語が分からないので、あなたに日本語でばかり話しかけてごめんなさい）
-I don't speak Taiwanese, that's why I speak Japanese to you all the time.
（台湾語が話せないので、いつもあなたに日本語で話しかけています）
-I'm sorry we only spoke in Japanese
（日本語でばかり話してごめんなさい）
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