入社1年目ビジネスマナーの教科書 改訂新版The Textbook of Business Manners for First-Year Employees (Revised Edition)Handy phrasebook for immediate use when you need the right words quickly.
日本語能力試験対策 日本語総まとめ N1 漢字Nihongo So-matome N1 KanjiPractical guide to master polite language for real-world business situations.