renkyuu ni wa tomodachi to issho ni kaigairyokou o shitai desu.

During a long holiday, I want to travel abroad with a friend.

Breakdown of renkyuu ni wa tomodachi to issho ni kaigairyokou o shitai desu.

• は: topic particle
• です: to be
• を: direct object particle
• 友とも達だち: friend

Questions & Answers about renkyuu ni wa tomodachi to issho ni kaigairyokou o shitai desu.

Why does 連休 have both に and は after it (連休には)? Wouldn’t just 連休に be enough?

連休に by itself simply means “during the long holiday / on the long holiday.”

Adding は as in 連休には does two things:

1. Marks the time phrase as the topic of the sentence:

   • 連休には、友達と一緒に海外旅行をしたいです。
     → As for the long holiday, I want to travel abroad with my friends.

2. Often adds a slight contrast or emphasis:

   • Implied: Maybe not at other times, but *during the long holiday, I want to travel abroad.*

You could say 連休に友達と一緒に海外旅行をしたいです, and it would still be correct and natural.
連休には just highlights that period a bit more, like saying “(Especially) during the holidays…”

Why is there a に after 一緒 (一緒に)?

一緒に is a fixed phrase meaning “together (with someone) to do something.”

The pattern is:

• A と 一緒に B を する
  → do B together with A

So in this sentence:

• 友達と = with friends
• 一緒に = together (adverb modifying the verb)
• 海外旅行をしたいです = want to travel abroad

All together:
友達と一緒に海外旅行をしたいです。
→ I want to travel abroad together with my friends.

You can’t drop the に here; 一緒に is treated like one word.

Isn’t and saying the same thing twice? Why both?