She's on the phone right now. Should I have her call you back?
She's on a different line right now. Can I have her call you back?
ここで違う言い方があるとすればまずは「[電話](https://eikaiwa.dmm.com/uknow/questions/51755/)」、又は「電話中」という表現ですね。
”on the phone" という最初の例で採用したそのままの直接的な表現や ”on a different line" （別の電話に出ている）という表現などが挙げられます。
同時に、”should I have her call you back?" （直訳：彼女に[折り返し電話するように](https://eikaiwa.dmm.com/uknow/questions/215/)言うべきですか？）→ （意訳：折り返しお電話するようお伝えしましょうか？）
という表現と、”Can I have her call you back?" （直訳：彼女に折り返し電話するようお伝えしてもいいですか？） → （意訳：折り返しお電話する形でも宜しいでしょうか？）
”can" を使うか ”should" がいいかの違いはあまり変わりませんのでその都度気分で言い換えてもいいと思います。
参考になればと思います♪
1. She's busy at the moment. Shall I ask her to call you back?
2. Sorry, she's otherwise engaged at the moment. Please give me your number and I'll ask her to call you back.
3. Sorry, she's unavailable. Would you like to leave a message?
I feel phrase 3 is the most professional response.
Giving details of what the coworker is doing may be seen by some people or some companies as a breach of confidence. People are either 'available' or 'unavailable'
Sorry, she is on the phone at the moment. Shall I/can I get her to call you back?
She is busy on a call at the moment, Can I take a message?
She is on the phone at the moment or busy on a call at the moment. Explains she is busy on the phone.
Can I or Shall I get her to call you back. asks them if they way you to tell her to call them back.
You could also ask they if you can take a message to pass on to her.
She is on the phone at the moment / busy on a call at the moment.
これは、彼女が電話中で忙しいというときに使う表現です。
Can I / Shall I get her to call you back.
これはかけ直しさせるかどうか尋ねる表現です。
何か言伝がないか尋ねてもいいですよね。
1. Sorry, she is on another call. Would you like her to return your call?
2. Sorry, she is on another call. Would you like to leave her a message?
1. "Sorry, she is on another call. Would you like her to return your call?" - To return a call means to call someone back.
2. "Sorry, she is on another call. Would you like to leave her a message?" - You can also ask if the caller would like to leave a message for your coworker. They can then respond with a message or commonly they will respond and say: "Yes, please ask her to call me back."
I hope this helps :)
"1. ""Sorry, she is on another call. Would you like her to return your call?”(すみません。彼女は今電話中です。後でかけさせ直させましょうか？) “return a call”とは誰かに電話をかけ直すという意味です。
2. ""Sorry, she is on another call. Would you like to leave her a message?”(すみません。彼女は今電話中です。彼女にご用件をお伝えいたしましょうか？) 電話をかけてきた人に同僚に伝言を残したいかを聞くことができます。すると彼らは伝言を残すか""Yes, please ask her to call me back.”(ええ、彼女に電話をかけ直して欲しいと伝えてください)といった一般的な返事をするかもしれません。
ご参考にしていただければ幸いです。"
She's on the phone right now, can I have her call you back?
To say that she is on the phone right now, is to say that she is taking a call from another person. To 'have her call you back' is to say that they will call you and you do not need to call again.
she is on the phone right nowとは、彼女が他の人からの電話を取っている状態です。
have her call you backは、彼女が折り返し電話をしてくれるので、あなたから電話をする必要はないということです。
She is unavailable right now, do you want to leave a message?
She is on the other line, I can ask her to call you back.
These are commonly used
"She is unavailable right now, do you want to leave a message?
ただ今電話に出る事ができません。伝言を残されますか。
She is on the other line, I can ask her to call you back.
ただ今別の電話に出ております。終わり次第かけなおすように伝えておきます。
上記二つの表現はよく使用されます。"
Hi, she just took a call on her cellphone, can I ask her to call you back?
Hi, she is on another. You can leave your name and number than I will get her to call you back.
▪ Hi, she just took a call on her cellphone, can I ask her to call you back?
This is telling the person that she is on her cellphone and can't take the call and that you will ask her to call you back.
▪ Hi, she is on another. You can leave your name and number than I will get her to call you back.
This is saying that she in not available to take the call but the person can leave there details and you will give you coworker the message.
Example 1
Client: Hello, can I speak to Mayu?
You: Hi, she just took a call on her cellphone, can I ask her to call you back?
Example 2
Client: Hello, is Mayu available?
You: Hi, she is on another. You can leave your name and number than I will get her to call you back.
▪ Hi, she just took a call on her cellphone, can I ask her to call you back?
（彼女は携帯電話で電話中ですので、かけなおさせましょうか？）
こちらの文は、彼女は携帯電話で電話中で、電話をとれないので、かけなおさせようか相手に尋ねています。
▪ Hi, she is on another. You can leave your name and number than I will get her to call you back.
（彼女は別の電話にでています。お名前と電話番号を残して頂ければ、かけなおさせます。）
こちらの文は、彼女が電話をとれない状態ですが、相手が詳細を残してもらえれば、あなたが彼女にメッセージを伝えると言っています。
例1
顧客: Hello, can I speak to Mayu?
（もしもし。まゆさんとお話しできますか？）
あなた: Hi, she just took a call on her cellphone, can I ask her to call you back?
（彼女は携帯電話で電話中ですので、かけなおさせましょうか？）
例2
顧客: Hello, is Mayu available?
（もしもし。まゆさんとお話しできますか？）
あなた: Hi, she is on another. You can leave your name and number than I will get her to call you back.
（彼女は別の電話にでています。お名前と電話番号を残して頂ければ、かけなおさせます。）
She is on the other line right now, can you call back?
Please call back in a few minutes, she is on another call.
Can I take the message, she is on the phone right now?
Examples
"Can I take the message, she is on the phone right now?"
or
"Please call back in a few minutes, she is on another call."
or
"She is on the other line right now, can you call back?"
"Can I take the message, she is on the phone right now?"
伝言を預かってもいいですか？彼女は今話し中です。
"Please call back in a few minutes, she is on another call."
数分後にかけ直してください。彼女は他の電話にでています。
"She is on the other line right now, can you call back?"
彼女は今、他の電話にでています。かけ直してもらえますか？
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