Discussing Your Plans in Tokyo

The use of particle に [ni]:

• Location + に [ni] / に marks the location as the endpoint of your journey.
• 日本に [nihon ni] to Japan
• 東京に [tōkyō ni] to Tokyo

• Action + に [ni] / に marks the action as the purpose.
• 食べに [tabe ni] in order to eat
• 勉強しに [benkyō shi ni] in order to study

本を読みに図書館に行きます [hon o yomi ni toshokan ni ikimasu]
I go to the library to read books.

• 本を読みに [hon o yomi ni] means "in order to read books"
• 図書館に [toshokan ni] means "to the library"
• 行きます [ikimasu] means "I go"
• Literally means "in order to read books, to the library, I go."

何をしに図書館に来ましたか [nani o shi ni toshokan ni kimashita ka]
What did you come to the library to do?

• 何をしに [nani o shi ni] means "in order to do what?"
• 来ましたか [kimashita ka] means "Did you come?"
• Literally means "In order to do what, to the library, did you come?"

• A: 今日はどこに行きますか
  Where are you going today?
• B: 今日はカフェに行きます [kyō wa kafe ni ikimasu]
  I'm going to a cafe today.
• A: 何をしにカフェに行きますか
  What are you going to do at the cafe?
• B: 勉強しにカフェに行きます [benkyōshi ni kafe ni ikimasu]
  I'm going to study at the cafe.
• A: 明日はどこに行きますか
  Where are you going tomorrow?
• B: 本を読みに図書館に行きます [hon o yomi ni toshokan ni ikimasu]
  I'm going to the library to read books.
• A: 一緒に行きましょう
  Let's go together.