一并 (yībìng) means 'together' but with a nuance of handling multiple items in a single action, often for documents, tasks, or expenses. It's more formal and procedural than 一起 (everyday 'together') and 一同 (joint action), and less dramatic than 一口气 (in one go, often for physical effort) or 一举 (at one stroke, implying a decisive move).