でいちばん

the most ... in

→ で
phrase Rare #20,746
the most ... in Used with a place or group to express the superlative: the most [adjective] in a particular place or among a particular group.
JA: この町でいちばん大きい公園はどこですか。
EN: Where is the biggest park in this town?

日本でいちばん高い建物は何ですか

What is the tallest building in Japan?

銀座日本でいちばんにぎやかな通りなのですか

Is Ginza the busiest street in Japan?

世界でいちばんいい仕事だもの

Because it’s the best job in the world, after all.

北米でいちばん高い山は何ですか

What is the highest mountain in North America?

日本でいちばん長いはどれですか

What is the longest river in Japan?

太平洋世界でいちばん大きな大洋です

The Pacific Ocean is the largest ocean in the world.

トム世界でいちばんハンサムな男優

Tom is the most handsome actor in the world.

この湖は日本でいちばん深いである

This lake is the deepest lake in Japan.

信濃川日本でいちばん長い

The Shinano River is the longest river in Japan.

日本でいちばんおいしい果物は

What is the most delicious fruit in Japan?