Verb "to organize"

Hi my great teachers!!

Would you please tell me the original sentence of the one bellow.

Everything to organize the picnic has already been done.

For example, the sentence like: The letter mailed today hasn’t arrived yet. This sentence originate from the one : The letter [color=red]which is mailed today hasn’t arrived yet,
right?

What about [color=red]to organize above where does from?

Thankssssssss!

Soklong

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Keep in mind that there is no ‘original sentence’. Potential words of an utterance can be elided through the mutual understanding of listener and speaker. Perhaps:

Everything [needed/required] to organize the picnic
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Hi soklong,

Everything to organize the picnic …

could simply be: Everything you want to organize …

Alan

Thank teachers!

But I still woder if it is said to be from the sentence like you said:

Why we omit needed/required from this sentence. What we call this style?

Like: The letter which is mailed today hasn’t arrived yet to the letter mailed today… we call reduce adjective clause.

Thank beforehand

Soklong

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This also is a reduced adjective clause. I had already reduced it a bit:

Everything [(that is) needed/required] to organize the picnic.

The extent of elision depends on how much the reader/listener can be expected to understand, I suppose.
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