I'm new here so I'm not completely au fait with the system.

我初来乍到，所以对这个系统还不完全熟悉。

《牛津词典》

You can say something like, "I remember you said something very interesting yesterday and wanted to talk about it some more, but I'm new here and don't remember your name yet. Would you mind telling me again?"

你可以这样说：“我记得你昨天说了一些有趣的事情，还想多谈谈，但我是新来的，还不记得你的名字。你介意再告诉我一遍吗？”

youdao

Sorry, I'm new here myself.

对不起，我也是才来这的。

youdao

Now, the company strikes another hit in Las Vegas with amazing innovations that will revolutionize the world of technological communication: the new version of i'm Watch and the launch of a new product, i'm Here.

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"I'm not coming here to be Samuel Eto'o, I'm somebody else, somebody new, but I will try to achieve as much as Eto'o, or even more, " he added.

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And I'm talking here about the new 3G mobile devices.

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