Learn Hardcore Japanese: kazokuzenin de bangohan wo tabemasu. - Our whole family eats dinner together.

It often gets translated as “with” here, but more precisely it means “as / in the group of”.
So 家族全員で ≈ “as the whole family” / “(we) as a whole family”.

Compare:

家族と晩ご飯を食べます。 – “I eat dinner with my family” (focus on having them as companions).
家族全員で晩ご飯を食べます。 – “The whole family eats dinner (together)” (emphasis on the family as a complete group).

In other contexts, で can mean “at (a place)” or “by/with (a tool)”, but here it’s the “as a group” usage.

Why is there no subject like 私 or 私たち in the sentence?

Japanese often omits the subject when it’s clear from context.

家族全員で晩ご飯を食べます。 is understood as something like “(We) eat dinner as a whole family.”
If you’re talking about your own family and your own habits, listeners will naturally assume the subject is 私たちは ("we") or うちは ("our family").

You could say 私たちは家族全員で晩ご飯を食べます, but it sounds a bit heavy and is usually unnecessary in normal conversation.

What exactly does 家族全員 mean? How is it different from just 家族?

家族 = “family”
全員 = “all members / everyone (in the group)”
家族全員 = “all the members of (my/our) family” → “the whole family”.

So:

家族で晩ご飯を食べます。 – “The family eats dinner (as a group).”
家族全員で晩ご飯を食べます。 – Emphasizes that every single family member is included.

全員 makes it clear that nobody is left out.

Why is it 家族全員 and not something like 全家族 or 家族全部?

Those alternatives are not natural in this context.

全家族 is rarely used and sounds off here.
家族全部 is understandable but not the most natural phrasing for “the whole family” as people; it’s more common with things (e.g. 本全部 “all the books”).

For people, Japanese typically uses:

家族全員
家族みんな (more casual)

So 家族全員で / 家族みんなで are the natural ways to say “as the whole family”.

What is the nuance difference between 家族全員で and just 家族で or 家族みんなで?

All three can translate as “with my family / as a family”, but the nuance changes slightly:

家族全員で – Slightly more formal/neutral; clearly emphasizes all members.
家族で – Just “as a family”; doesn’t explicitly say all, though it’s often understood as everyone.
家族みんなで – Very natural and slightly casual; “all of us in the family”.

In many everyday situations, 家族で晩ご飯を食べます and 家族みんなで晩ご飯を食べます would be the most common.

What does 晩ご飯 mean exactly, and how is it different from ご飯 or 夕飯?

晩ご飯（ばんごはん） = “dinner” (evening meal).
ご飯 by itself can mean:
- “cooked rice”, or
- “a meal” in general (which meal is understood from context).
夕飯（ゆうはん） or 夕ご飯（ゆうごはん） also mean “dinner”; they’re roughly synonyms of 晩ご飯.

So in this sentence, 晩ご飯 is specifically the evening meal, “dinner/supper”.

Can I change the word order, like 晩ご飯を家族全員で食べます?

Yes. Japanese word order before the verb is quite flexible. These are all natural:

家族全員で晩ご飯を食べます。
晩ご飯を家族全員で食べます。

Both mean the same thing.
Often, information you want to highlight is placed earlier, but in everyday speech both orders are fine and common.

Why is を used after 晩ご飯? Can it be left out?

を marks the direct object of the verb.

晩ご飯を食べます。 = “(I/we) eat dinner.” → 晩ご飯 is what is eaten, so it takes を.

In very casual speech, you might hear 晩ご飯食べます without を, but in correct standard Japanese (and especially when learning), it’s better to include を.

You cannot replace を here with が or は without changing the structure/meaning.

Does 食べます here mean “eat” now, “will eat”, or “usually eat”?

Japanese ～ます / ～る (non-past) covers both present and future, and also habitual actions. Context decides:

Habit: “We eat dinner as a whole family (as a routine).”
Future/specific time (with a time word, e.g. 今日 / 今晩): “(Tonight) the whole family will eat dinner (together).”

So 食べます can be “eat”, “will eat”, or “(usually) eat”.

What’s the difference between 食べます and 食べる here?

They are the same verb with different politeness levels:

食べます – Polite form (used with people you aren’t close to, in formal situations, etc.).
食べる – Plain form (used with friends, family, diaries, casual writing).

So you could say 家族全員で晩ご飯を食べる。 casually, but 家族全員で晩ご飯を食べます。 is the polite version.

How do you pronounce each part of the sentence, and is there any reading trick?

Pronunciation (with romaji):

家族 – かぞく – kazoku
全員 – ぜんいん – zen’in
で – で – de
晩ご飯 – ばんごはん – bangohan
を – を – o (pronounced “o”)
食べます – たべます – tabemasu

So the whole sentence is:
かぞくぜんいんでばんごはんをたべます。

Note that を is almost always pronounced “o”, not “wo”, in modern Japanese.

In what kind of situation would someone naturally say 家族全員で晩ご飯を食べます。?

Typical uses include:

Describing a habit:
- “On weekdays, we eat dinner as a whole family.”
Explaining a plan:
- “Tonight, my whole family is going to have dinner together.”

Usually, a time expression (like いつも, 毎日, 今晩, 週末に) would be added in real conversation for clarity:

いつも家族全員で晩ご飯を食べます。
今晩は家族全員で晩ご飯を食べます。