syokutaku de kazoku to issyo ni bangohan wo taberu to, siawase wo kanzimasu.

で marks the place where an action happens. Since 食べる is an action, 食卓で means at the table or at the dining table as the location of eating.

Compare:

• 食卓で食べる = eat at the table
• 食卓にある = be on the table

So で is used because the sentence is talking about where the eating takes place.

家族と一緒に means together with my family or with my family.

The two parts work together:

• 家族と = with family
• 一緒に = together

Using both is very natural in Japanese and emphasizes doing something together rather than just being in the same place. You could say 家族と晩ご飯を食べる, but 家族と一緒に sounds a little warmer and more explicit.

This と is not the with particle. It is a conditional/connecting と.

In this sentence, 食べると、幸せを感じます means something like:

• when I eat ..., I feel happy
• if I eat ..., I feel happiness
• eating ... makes me feel happy

So here と connects the first clause to the result in the second clause.

A helpful way to see the structure is:

• 食卓で家族と一緒に晩ご飯を食べると = when I eat dinner together with my family at the table
• 幸せを感じます = I feel happiness

In this sentence, when is usually the most natural interpretation.

The と conditional often expresses a natural or regular result:

• AとB = when A happens, B happens / if A happens, B happens

Here the idea is not really a hypothetical condition like If I were to eat.... It is more like a general emotional result:

• When I eat dinner with my family at the table, I feel happy.

So when or whenever fits well.

They are similar, but not identical.

• 幸せです = I am happy.
• 幸せを感じます = I feel happiness.

幸せを感じます focuses on the experience of feeling happiness. It sounds a little more reflective or emotional.

So the sentence is not simply stating a permanent condition. It is saying that this situation causes the speaker to feel happy.

Yes, it is natural. It is a standard way to express feel happiness or feel happy.

That said, depending on context, native speakers might also say things like:

• 幸せです = I’m happy.
• 幸せな気持ちになります = It makes me feel happy.
• 幸せを感じる = feel happiness

In your sentence, 幸せを感じます works well because it matches the idea that the dinner situation leads to that emotion.

を marks the direct object of the verb 食べる.

So:

• 晩ご飯を食べる = eat dinner

The thing being eaten is 晩ご飯, so it takes を.

All of them can mean dinner/evening meal, but their tone is a little different.

• 晩ご飯（ばんごはん）: casual, everyday, very common
• 夕飯（ゆうはん）: also common and casual
• 夕食（ゆうしょく）: a bit more formal or neutral

In this sentence, 晩ご飯 fits nicely because the whole sentence has a warm, family-life feeling.

Japanese often leaves out the subject when it is clear from context.

In English, you usually need to say I feel happy. In Japanese, the speaker can simply say:

• 幸せを感じます

and the listener understands that the speaker means I feel happiness unless context suggests someone else.

So the sentence could be expanded to:

• 私は、食卓で家族と一緒に晩ご飯を食べると、幸せを感じます。

But 私は is not necessary.

The sentence follows a very normal Japanese pattern: context/details first, main result at the end.

You can break it up like this:

• 食卓で = at the table
• 家族と一緒に = together with my family
• 晩ご飯を = dinner
• 食べると = when I eat
• 幸せを感じます = I feel happiness

So the main verb of the whole sentence is 感じます, and everything before it sets up the situation.

The comma after 食べると helps separate the two parts of the sentence:

• the situation/condition: 食卓で家族と一緒に晩ご飯を食べると
• the result: 幸せを感じます

It makes the sentence easier to read, especially because the first part is fairly long. In Japanese, commas are often used for readability and rhythm, so this comma is natural, though punctuation can be somewhat flexible.

Yes, but the nuance changes.

• 食卓 = dining table; often has a homey feeling
• テーブル = table; more general, borrowed word
• 食堂 = dining room/cafeteria

In this sentence, 食卓で specifically gives the image of sitting around the family table. That fits very well with the emotional tone of the sentence. 食堂で would mean more like in the dining room, and テーブルで would be more general.

Yes, it can.

• 家族と晩ご飯を食べる = eat dinner with my family
• 家族と一緒に晩ご飯を食べる = eat dinner together with my family

Without 一緒に, the meaning is still clear. With 一緒に, the sentence puts more focus on the shared experience of being together, which matches the idea of feeling happiness.