Sorry? / Pardon me? / Excuse me?
您说什么?
I'm sorry, I didn't hear/catch you.
不好意思，我没听懂您的意思.
I didn't understand. Could you repeat that?
没听懂，能再讲一遍吗?
Could you speak up a little?
您大声点好吗?
I didn't understand what you are trying to say.
我不明白您要说的。
Could you explain with some examples?
您能举例解释一下吗?
Can you say again, please?
您能再重复一次吗?
Come again, please?
再说一次好吗?
I’m sorry?
请再说一次。