英语中听不懂其中一个单词应该怎么问

1.what`s the meanning of"x"?
2.I don`t understand. I`ve no idea.
3.let me see.
4.excuse me,what`s this?

1 Pardon.
Could you please repeat all after XXX(那个你听不懂单词前面的内容)

2 I can't catch up with you.
I can't follow you.
I don't get it.

3 Where is it? Mmmm, let me see…

4 Excuse me. Could you help me？ What is this?
I've never seen it before.

1.what is the meaning of that word?
2.I can't follow what you have said
3.let me think about it
4.excurse me ,what is this?

Sorry, I can't understand your last word.

1.如果和外国人在交谈，突然他说起一个单词我听不懂，我想问这个单词是什么意思应该怎么问。

what's meaning of XXX?

2.比较口语话的“我听不懂你在说什么”或者“我没有听懂”怎么问。

i don't understant what are you talking about?

3.有人找你借东西，你不记得放在哪里了，用英文说“让我想想看”怎么说

let me think about it.
let me see

4.有一个问题想问别人，“请教一下，这是什么东西”怎么问
excurse