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beginning (of writing); opening passage (sentence, paragraph, etc.)
本の書き出しが気に入った。
I liked the opening of the book.
レポートの書き出しを何度も書き直した。
I rewrote the opening of the report many times.
小説の書き出しの一文は読者の関心を引く上で非常に重要だ。
The opening sentence of a novel is extremely important for capturing the reader's interest.