noun
long sentence
Refers specifically to a single sentence that is long, often in the context of grammar or writing advice.
この文章は長文が多くて読みにくい。
This text has many long sentences and is hard to read.
長文を書くときは、主語と述語の関係に注意しよう。
When writing a long sentence, pay attention to the subject-predicate relationship.
noun, noun which may take the genitive case particle 'no'
long piece of writing; long text
Covers any extended written material: passages, letters, articles, telegrams, etc. Often used with の to modify nouns.
彼から長文の手紙が届いた。
I received a long letter from him.
長文のレポートを提出しなければならない。
I have to submit a long report.