"What are you laughing about?"
You are asking what the person finds to be funny.
"What are you giggling about over there?"
Giggling - This is a nervous or a quiet laugh. Laughing tends to be loud, while giggling is quiet.
Over there - You are addressing a person who might be on the other side of the room, train, etc.
"What are you laughing about?"
何に笑っているの？
その人が何がそんなにおもしろいのかを聞くフレーズです。
"What are you giggling about over there?"
そこで何にくすくす笑っているの？
Giggling - くすくす、静かに笑うこと。Laughingは、大きな声で笑うことに対して、gigglingは静かに笑うことを意味します。
Over there - 部屋や電車など自分の反対側のこと、向こう側という意味です。
People laugh for many reasons - sometimes maliciously, or in order to irritate or offend. How you react to that is up to you, but here are two typical UK responses to that kind of situation.
Both replies have the same meaning, and can be used in this situation. Laughing is the act of physically laughing when you hear or see something funny. Either question should get you the same response.
When someone is laughing for a reason unknown to you, and it seems like they are laughing at you; then you can say:
-Care to share the joke?
-What's so funny?
-Is anything the matter? I'd like to know what's so funny?
誰かが自分にはわからない理由で笑っていたり、自分に対して笑っているような気がするときに使うフレーズです。
-Care to share the joke?
その冗談教えてもらえる？
-What's so funny?
何がそんなに面白いの？
-Is anything the matter? I'd like to know what's so funny?
どうしたの？何がそんなに面白いのか知りたいわ。
Something that is humorous, funny, or amusing is something that makes you smile or laugh.
When someone is laughing at you, you can ask them "May I ask what is so funny?", "May I ask what is so humorous?", or "What is so amusing?".
「humorous」「funny」「amusing」は「（物事が人を）笑顔にさせる、笑わせる」という意味です。
自分のことを笑っている人がいた時には：
"May I ask what is so funny?"（何がおかしいんですか？）
"May I ask what is so humorous?"（何がおかしいんですか？）
又は
"What is so amusing?"（何がそんなにおかしいの？）
と言えます。
"Why are you laughing?" and "What's so funny?" are two different ways to ask someone why they are laughing at you. In order for it to sound irritated or confused, that depends on how you say it. English does not have a set way to say something that tells the person you are annoyed, rather it is your tone of voice (how you say it) that will determine if you are irritated or confused or annoyed.
"Why are you laughing?"（何で笑うの）
と、
"What's so funny?"（何がおかしいの）
はどちらも、「どうして私を笑うのか」と相手に尋ねる言い方です。
いら立ちや困惑した気持ちは言い方によって表します。英語には腹を立てていることを表す決まった言い方はありません。いら立ちや困惑、怒りは声のトーンによって表します。
Starting with 'hey' is a method of getting their attention in a serious way.
This will notify them that you are aware they are laughing at you and you would like to know why.
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