食べる＝英語では eat じゃないの？
「物を食べるって言いたいとき、日本人は大抵 eatって言うけど、英語を聞いてると have って言っていることが多い気がする。何が違うの？」という質問を受けました。
確かに、私もそういう場合は have を使っており、eatはあまり使わないかも。それで、改めて違いを調べてみました。
以下、VOA learning Englishからの抜粋です。
When talking about a specific meal or food, the verbs “eat” and “have” are often interchangeable. That means either word can be used.
Listen to an example of when to choose either word:
I’m having breakfast right now. I’ll see you in a little while.
I’m eating breakfast right now. I’ll see you in a little while.
In the example, most Americans would probably use “eat” but “have” would still sound natural. And there is no different in meaning between the two.
☞ 特定の食べ物について話している場合は、eatとhaveはinterchangeable（互換的に使える）。
Polite requests
But the word “have” is used in polite or kind requests and offers that relate to food and meals. In these cases, often the eating does not take place at home.
Here’s an example of a kind offer from a friend:
Want to have dinner at my place? I’m making grilled fish.
We also use “have” when ordering food at a restaurant. It does not matter what kind of restaurant it is. We do not use eat.
Listen to this short restaurant exchange:
Good morning, what will you have?
We will have the oatmeal, thanks.
☞ 食べ物や食事に関する丁寧な依頼の場合はhaveを用いる。また、レストランでの注文の際は必ずhaveを用いる。
Transitive, intransitive
Here is something else to consider when choosing one or the other:
The verb “have” is transitive. That means we must always say what we ate or will eat. For instance, in the restaurant exchange, the man said they would have the oatmeal.
“Eat” is intransitive, which means we do not have to say it. So, you can say this:
I’m really hungry. Let’s eat!
But you cannot say, “I’m really hungry. Let’s have!” You can, however, say:
I’m really hungry. Let’s have pasta!
☞ haveはtransitive（他動詞）、つまり、何を食べた（食べる）かを言う必要があるが、eatはそうではない。例：Let’s eat!で文を終えることはできるが、let’s have!とは言えず、食べる対象も言う必要がある。つまり、Let’s have pasta!など。
