不客气，这是我应该做的

The phrase '不客气' (bú kèqi) literally means 'no need to be polite' or 'don't be so formal.' It's a very common and versatile way to say 'you're welcome' in Chinese. The addition of '这是我应该做的' (zhè shì wǒ yīnggāi zuò de) translates to 'this is what I should do' or 'it's my duty/pleasure.' This extended phrase adds a layer of humility and downplays the effort involved, suggesting that helping the other person was not a burden but rather a natural or expected action. It emphasizes that the speaker considers the act of helping as part of their responsibility or a small matter. This cultural nuance of minimizing one's own efforts is common in Chinese etiquette, where it's often seen as more polite to appear modest. The phrase can be used in a variety of contexts, from simple favors to more significant acts of kindness, and it always conveys a sense of graciousness and approachability. It stands in contrast to more direct or transactional 'you're welcome' phrases, highlighting the relational aspect of the interaction.