So i'm trying to figure this out why you put a の with a 作る(to make)...i.e.
mary さんはすしをつくるのがへだです...
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2017-04-30T03:04:28.277
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2017-04-30T03:59:59.370
2017-04-30T03:26:15.457
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question
usage particles particle-の
Where does the 'no' come from in tsukuru(no)? Is it a particle or part to tsukuru
の is used to make a noun clause just like こと is.  
For this function, の and は are roughly interchangeable.

I think の is more frequently used than こと in daily conversation, because の
could be pronouced more easily than the other.
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2017-04-30T03:34:03.447
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2017-04-30T03:56:11.640
2017-04-30T03:56:11.640
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answer
In order to describe a verb or add more sentence onto a verb you have to first
turn it into a noun, with either の or こと. So, here the whole phrase すしをつくる
acts as one noun when の is attached, and then you just continue as normal.
～がへたです。

Other examples of this same this happening:

本を読むのが好きです 読む + の

やったことないです。 （やる）やった + こと

そうなんです。 （です・だ）な + ん（の）
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2017-04-30T03:59:59.370
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answer