In Japanese, when expressing the superlative form of an adjective, the adverb ichiban ("most," literally, "number one") is place just before the adjective. The limit within which the comparison is made, the things among which one thing is the "most" or the "best" is indicated by the particle de. However, if the limit is representing a group of people, the phrase no naka de ("among," "of all...") is used instead.
Fujisan wa Nihon de ichiban utsukushī yama da/desu.
Mt. Fuji is the most beautiful mountain in Japan.
Kono tera wa Nara de ichiban furui desu.
This temple is the oldest in Nara.
Furanku wa kurasu de ichiban yūshūna gakusei datta.
Frank was the best student in the class.
Hisho no naka de, Yasuda-san ga ichiban yūnōdesu.
Of all the secretaries, Ms. Yasuda is the most competent.
Hope this helps, and see you again！
°˖ ✧◝(○ ヮ ○)◜✧˖ ° こゆうきあいはら °˖ ✧◝(○ ヮ ○)◜✧˖ °