「円で」は
❶With Japanese yen
❷ In Japanese yen、どちらでもオッケーです。
例えば、
When I used my Japanese credit card, it asked me if I wanted to pay in Japanese yen or the local currency.
(日本のクレジットカードを使った時、円で払いたいのか、現地通貨で払いたいのか、聞かれた)。
When I used my credit card, I could choose to pay with Japanese yen or the local currency, so I chose to pay with Japanese yen.
(クレジットカードを使った時、円か現地通貨で払うか 選べたので、「円」にした)。
*Local currency 現地通貨
と言えますよ、参考に！
When paying by credit card, and when asked whether you'd like to pay in Japanese yen or the local currency, you want to choose yen. Any of the above example sentences will be adequate for this context.
When you are asked to choose the currency while using a credit card to charge something (when you are in a foreign country), you can respond by saying "Pay with Yen, please.
外国にいて、クレジットカードの支払いのときに通貨を選ぶように言われたら、"Pay with Yen, please."（日本円で支払いをお願いします。）と言うといいでしょう。
こんにちは。
下記のように表現することができます。
・Yen, please.
「円でお願いします」
こちらはシンプルな言い方です。
In yen, please でももちろんOKです。
より丁寧に全部言いたい場合は：
・I'd like to pay in yen.
私は円で支払いたいです。
ぜひ参考にしてください。
I want to pay in my country's currency on my card.
Please convert the currency to Yen.
Please choose the currency as Yen.
When you are paying with your credit card and the salesperson asks whether you want to pay in the local currency or in Yen, then you would say, "I want to pay in Yen, please."
Ex: Waiter: Would you like to pay in dollars or in Yen?
You: I want to pay in Yen, please.
クレジットカードで支払いたくて、お店の人が現地通貨で支払いたいか、日本円で支払いたいかを聞いてきたら、"I want to pay in Yen, please."（日本円でお願いします。）と言うといいでしょう。
例：
Waiter: Would you like to pay in dollars or in Yen?
（ウエイター：ドルと日本円どちらで支払いますか？）
You: I want to pay in Yen, please.
（あなた：日本円でお願いします。）
I'd like to pay in Yen please
Make that Yen please.
Both these responses are pretty simple and easy enough
for the listener to understand that you would like to pay for
your purchases in Japanese Yen.
I'd like to pay in Yen please
（日本円での支払いをお願いします。）
Make that Yen please.
（日本円でお願いします。）
これらはどちらも、相手に日本円で支払いたいことをシンプルに伝えることができるフレーズです。
When making a credit card purchase, you can indicate your preferred currency of payment by asking to be charged in that particular currency. For example: Can you please charge me in Egyptian pounds? Can I pay in Japanese Yen? In some situations the credit card machine will require you to make that choice manually. This usually involves reading the screen (in English) and pressing a button corresponding to the currency of your choice. You can also use the subjunctive "would" as a polite way of indicating your preference.
I would like to pay in US dollars.
When a person asks whether you would prefer to pay in their local currency or in Japanese yen, then you may respond by saying:
-I would like to pay in yen
-Yen!
-Yen, please.
-I'll be paying in Japanese yen
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