rainen no kaigairyokou ni tuite, kazoku to soudansimasu.

の links two nouns and shows that the second noun is being specified by the first.

• 来年 = next year
• 海外旅行 = overseas trip / trip abroad
• 来年の海外旅行 = next year’s overseas trip

So here, 来年 is modifying 海外旅行.

You can think of it as:

• the overseas trip for next year
• next year’s overseas trip

について means about, concerning, or regarding.

So:

• 海外旅行について相談します = discuss/consult about the overseas trip

If you used を, it would sound like overseas trip is the direct object of the verb, but 相談する usually takes the topic with について when you want to say what the discussion is about.

A very natural pattern is:

• A について 相談する = to discuss/consult about A

について attaches to a noun and marks it as the topic or subject matter.

In this sentence:

• 来年の海外旅行について = about next year’s overseas trip

It is very common in Japanese when talking about:

• discussing something
• learning about something
• writing about something
• thinking about something

Examples:

• 日本の歴史について勉強します。 = I study about Japanese history.
• 将来について考えます。 = I think about the future.

The comma separates the topic phrase from the main action:

• 来年の海外旅行について、家族と相談します。

It helps the sentence read more clearly, especially because the first part is a long phrase.

It is similar to a pause in English:

• As for next year’s overseas trip, I’ll discuss it with my family.

The comma is natural, but not always absolutely required.

Here, と means with.

• 家族と相談します = I will discuss it with my family

So と marks the person or group you are having the discussion with.

This is a common use of と:

• 友だちと話します。 = I talk with my friend.
• 先生と相談します。 = I consult with my teacher.

Good question. 相談する can appear with both に and と, but the nuance is a little different.

• A に相談する = to consult A, often asking A for advice
• A と相談する = to discuss with A, more like having a mutual conversation

So:

• 家族に相談します can imply I will ask my family for advice
• 家族と相談します can imply I will discuss it together with my family

In this sentence, と makes sense because family trips are often something everyone talks over together.

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

So even though 私 is not written, the sentence can still naturally mean:

• I will discuss next year’s overseas trip with my family

This is very normal in Japanese. If the speaker is obvious from the situation, you usually do not need 私.

Japanese -ます forms do not mark the future separately the way English does.

So 相談します can mean:

• discuss
• will discuss
• am going to discuss

The exact time depends on context.

Because the sentence mentions 来年 and sounds like a plan, the natural English meaning is usually future:

• I will discuss next year’s overseas trip with my family.

Yes.

• 旅行 = trip / travel
• 海外旅行 = overseas trip / travel abroad

海外 means overseas or abroad, so 海外旅行 is specifically travel to another country.

If you only say 旅行, it could be domestic or international.

In Japanese, 家族 by itself often means my family or one’s family, depending on context.

So in this sentence:

• 家族と相談します

the natural understanding is:

• I’ll discuss it with my family

Japanese often does not use possessives like my when the meaning is already obvious.

Yes, somewhat. Japanese word order is more flexible than English, as long as the particles stay correct.

This sentence:

• 来年の海外旅行について、家族と相談します。

could also be rearranged in some contexts, such as:

• 家族と来年の海外旅行について相談します。

Both are natural. The difference is mostly about emphasis and flow.

The version with 来年の海外旅行について first puts the topic up front:

• About next year’s overseas trip, I’ll discuss it with my family.

Japanese sentences usually place the main verb at the end.

So the structure is roughly:

• 来年の海外旅行について = about next year’s overseas trip
• 家族と = with my family
• 相談します = discuss / will discuss

This is one of the most important patterns in Japanese:

• information first
• main action last

No. Normal Japanese writing usually does not use spaces between words.

This sentence would normally be written as:

来年の海外旅行について、家族と相談します。

Spaces are often added only in beginner materials to make word boundaries easier to see.