帮帮 is the reduplicated form of the verb 帮 (to help). In Chinese, reduplicating a monosyllabic verb (V-V pattern) softens the tone, making the action sound more casual, brief, or polite. It is often used when making a request or suggesting that someone help in a light or temporary way. For example, 你帮帮我 (nǐ bāng bang wǒ) means 'Could you give me a hand?' rather than a strong command.