Could you do me a favor?
请问你可以帮我一个忙吗？

Could you bring me something special back?
请问你能给我带回来一些新奇的东西吗？

Could you help me with something?
请问你能帮我做点事情吗？

A:Hey,how are you doing?
你好！最近过得怎么样？

B:Could you do me a favor?
请问你可以帮我一个忙吗？

A:Sure,whatever you need.
当然没问题。

B:Can you help me move this table.
你能帮我移一下这张桌子吗？