Grammar Info
N3 Lesson 10: 19/20

は~となっている
it is (has been), have/has become, happen to be, has been established

Structure
Casual
Polite
[な]Adjective + なっている
Noun + なっている
[な]Adjective + なっています
Noun + なっています
Details
Register Formal
使用域 硬い
Information
(A) は (B) となっている is a common expression used to show that ‘(A) is becoming (B)’, or (more commonly) ‘(A) has become (B)’. This expression will only appear with nouns, or な-Adjectives in their 語幹(ごかん) (stem form). (A) は (B) となっている is often translated as ‘(A) happens to be (B)’, ‘(A) has been established as (B)’, or ‘it has been decided that (A) is (B)’.
Let’s have a look at some examples, and then how this structure is formed.
  • 鬼滅(きめつ)刃(やいば)非常(ひじょう)人気(にんき)となっている
    It happens to be that Demon Slayer is very popular.
  • 日本(にほん)ドラッグは法律上(ほうりつじょう)、違法(いほう)となっている
    In Japan, it has been established that drugs are illegal, by law.
  • このプールで、飛(と)び込(こ)み禁止(きんし)となっている
    At this pool, it happens to be that jumping in is not allowed.
Despite the different translations, (A) は (B) となっている always has the same meaning, which can be understood as follows:
(A) は - (A) is a constant unchanging thing.
(B) と - (B) is a result. (coming form the 格助詞(かくじょし) (case marking particle) と’s role in highlighting results.
なっている - (A) is existing in the state ‘having arrived at the result of (B)’.
  • 今(いま)時代(じだい)にインターネット必要(ひつよう)となっている
    It is now that the internet is necessary in the present age.
  • この高校(こうこう)アルバイト禁止(きんし)となっている
    It is now that working part-time at this school is prohibited.
Due to this, the literal translation may be thought of as ‘it is now that (A) is (B)’ in almost all situations.
Caution
(A) は (B) となっている may be rephrased to (A) は (B) になっている. However, will remove much of the feeling of a ‘result’, or ‘finiality’. Due to this, it will just sound like (A) is becoming (B), but is not necessarily that way yet.
  • 今(いま)時代(じだい)にインターネット必要(ひつよう)になっている
    It is now that the internet is becoming necessary in the present age.
Caution
In writing, おる is not always considered a ‘formal’ equivalent of いる, especially in set phrases. となっている is often seen as となっており, instead of となっていて. This is particularly common in news articles.
  • このイベントは来月(らいげつ)5日(か)からとなっており、明日(あした)から前(まえ)売(う)り券(けん)買(か)うことができる
    It is now that next month's event from the 5th has pre-order tickets that are purchasable from tomorrow.
Slow Male
Hide All
Hide Japanese
Hide English
いくつかの州(しゅう)では21才(さい)未満(みまん)の子供(こども)たちや若者(わかもの)がアルコールを消費(しょうひ)すること違法(いほう)となっている
In some states, it has been established that the consumption of alcohol by children and young adults under 21 is illegal.
だ・です・である can be used here, but without the 'become' nuance.
Play  
フランツ・フェルディナント大公(たいこう)の暗殺(あんさつ)開戦(かいせん)の原因(げんいん)の一(ひと)つとなっている
The assassination of Archduke Franz Ferdinand has been established as one of the causes of war.
だ・です・である can be used here, but without the 'become' nuance.
Play  
アメリカをはじめとして、電気(でんき)主要(しゅよう)な光源(こうげん)となっている
Starting with the USA, electricity has become the main source of light.
だ・です・である can be used here, but without the 'become' nuance.
Play  
Online
Books
Tobira
Page 147