ykさんへ
既に先の回答者様がアドバイスされている内容が
ございますので、私からは追加で紹介致します。
何か聞いてもらいたい話題やニュース、噂話などを
切り出す時に、
You know what? ねえちょっと、知ってる？
というフレーズが使えます。
日本語には訳しずらいのですが、「ちょっと聞いてよー」
というシチュエーション（＝今から言おうとしていることに
相手の注意を引きたい場面）にはぴったりです。
（典型的な使用例です）
A: You know what? Brian is going to get married!
B: Is that true!?
※You know what↑と、疑問文のようにイントネーションを上げて言います。
A: You know what? Takashi is going to study abroad next year.
B: Oh, really?
A: My boss has just told me to give a presentation about my ideas next week.
「上司が、私のアイディアについて来週プレゼンをするよう言ってきたんだ」
B: That's a big chance, isn't it? 「それって、大きなチャンスじゃない！」
A: It is, but ... you know what?
I've never made a presentation in front of a lot of people...
「でも ... ちょっと聞いて。大勢の前でプレゼンなんてしたことないんだ ... 」
・・・以上、お答えになっておりますでしょうか。
少しでも参考として頂けますと幸いです。
ykさんの英語学習の成功を心より願っております。
LLD外語学院 学院長 前川 未知雄
Pst! I have something to tell you. - Pst! is the sound you make to get someone's attention. You can then tell them that you wanted to tell them something by saying "I have something to tell you."
Yo! Whaddup? / Yo! Listen up! / Yo! Guess what? - You can use this with friends only. "Yo!" means hey and "whaddup" means what's up but also listen up.
Pst! I have something to tell you. = Pst! は誰かの注目を集めたい時に出す音です。
I have something to tell you.
（話したい事があるんだ）
と言うことで、話を切り出せます。
Yo! Whaddup? / Yo! Listen up! / Yo! Guess what? -これはカジュアルな表現なので親しい友人間のみで使えます。
”Whaddup” は ”What's up?"（調子はどう？）という意味もありますが、「ちょっと聞いて」という意味でも使えます。
Hey...you'll never guess what happened, on the way to work this morning!
Piquing someones curiosity is a great way to get their attention ...
and the set up:"You never guess what happened...".... never fails for me ;-))
Hey...you'll never guess what happened, on the way to work this morning!
誰かの好奇心を刺激することは、注意を引くとても良い方法です。
"You never guess what happened."と言うと、私の場合はいつもうまくいきます。
例文：
Hey, you'll never guess what happened, on the way to work this morning!
（ちょっと聞いてください。今朝仕事に向かう途中で何があったと思いますか。）
This is a common way to inform someone that you want to tell them something.
If you use "need' it shows that it is important and if you use that word you definitely their attention.
It depends exactly on the situation. The above answers would be good in a restaurant situation or similar...or when asking an official for information if they are distracted or involved in doing a task.
I would like to speak to you./Could I have a moment of your time?
Listen up!
"Sorry/excuse me, Can you listen to me."
"sorry or excuse me" will get the persons attention.
"Can you listen to me." Asks them to listen to what you are saying. This is normally used when someone is distracted and paying attention to things around them.
"I would like to speak to you./Could I have a moment of your time?" Both these ask a person before have if you can speak to them.
"Listen up!" Is a way of getting peoples attention when in a room full of people.
例文
"Sorry/excuse me, Can you listen to me."
すみませんが、私の話しを聞いて頂けますか？
"sorry or excuse me" と言って人の注意を引きます。
"Can you listen to me？"と言って私の話しを聞くように頼んでいます。この表現が一般的に使われるのは、注意力が散漫で、他のことに気を取られている時です。
例文
"I would like to speak to you./Could I have a moment of your time?"
ちょっとお話をしたいのですが。お時間少しよろしいですか？
両方の表現とも、話しが出来るかどうかを尋ねています。
例文
"Listen up!"
聞いて下さい。
部屋に人が一杯いる時に人の注意を引く言い方です。
Have you heard the news? We will get a 10% salary increase this year!
Hello! I need to tell you something.
The phrasal verb 'listen up' is usually used in the US when someone has something to say to somebody or a group of people to make them pay attention to what he/she has to say.
Listen up everyone! I have good news for you. Everyone will get a 10% salary increase this year1
Sometimes you might have heard very important news the source of which not everyone has access to.
So, you may say:
Have you heard the news? We will get a 10% salary increase this year!
The exclamation 'hello' is one good word to use when you need to attract someone's attention.
You may say:
Hello! I need to tell you something.
Hello! You have a visitor at the main gate.
'listen up' というフレーズは、アメリカでは誰かに何かを言いたいとき、自分が言うことに注目してもらう表現です。
Listen up everyone! I have good news for you. Everyone will get a 10% salary increase this year!
みんな聞いて！うれしいお知らせがあります。全員、今年給料が10%あがります！
みんなが知っているわけではないとても大事な情報を聞くことがあるかもしれません。そういう時は以下のように表現できます。
Have you heard the news? We will get a 10% salary increase this year!
このニューズ聞いた？今年10%、給料があがるんだって！
'hello' と強調して言うのも、誰かの注意を引けるいい方法です。
Hello! I need to tell you something.
ねぇ！言わないといけないことがあるんだけど。
Hello! You have a visitor at the main gate.
ねぇ！メインゲートにあなたのお客さんが来ているわよ。
The most common way to grab someone's attention would be to say, "listen up," however we can also say, "guess what," when we are about to tell someone information that they don't actually know. We can also directly say, "I have something to tell you," when we are announcing something that we want them to pay attention to.
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南アフリカ 
