で at the end of the sentence

[raikado]

Hello,

So, today I've encountered this(it's a girl talking, if it matters): 一緒に、私の姉妹を捜しませんか？ といってもー 主に桂木（かつらぎ）くんが中心で。

My translation is something like: "Wouldn't you help me search for my sisters? Even if I say this...You are, for the most part, the central part of all this."; I guess the intent is that she is telling him that he is already too deep in the matter and there is no way he could refuse.

Anyway, what bothers me is で at the end there. This is not the first time I've encountered this, but until now I've dealt with it by interpreting the sentence as being incomplete, and that the rest is left out. But I'm starting to doubt this, mostly because of the full stop at the end. I think this で it's just the same as だ, but it's only used like this in colloquial speech.

When I searched I only found people asking for sentences ending in verbs in te form, while this で feels different.

Also, here's a sentence I found yesterday: 私と・・・話しませんか？ 天理（てんり）には秘密で。Again, it fits to replace it with だ. "Can you talk to me? Tenri doesn't know about this. (This is a secret for Tenri)".

So, is this で the same thing as だ? And if so, is there any reason why one would use で instead of the grammatically correct だ?

 

[Mike Cash]

で at the end of the sentence

Add 探すto the end of the sentence and it should become clear.

Add 話して to the other one.

 

[Toritoribe]

As for the second example 私と…話しませんか？天理には秘密で, it's an inversion (天理には秘密で、私と話しませんか？). Grammatically, two different interpretations, the -te form of copula and the particle to indicate a state of action, are possible regarding this で. The difference in meaning is subtle, though.

 

[raikado]

Ahh...So my theory was wrong after all.

Well, the thought didn't even cross my mind that I could add 探す in the first one. I think I understand the pattern now.

Thank you for your answers.