"such ... as" and "such ... that" combined?

[zhanghuck83]

I came across the following exercise and found it a little awkward.
Exercise: They are such beautiful vases ______ everybody wants to buy ______ they are sold out in less than half an hour.
Key: as; that
This exercise combines "such ... as" structure （relative clause） and "such ... that" structure (adverbial clause).
Can the two structures be combined this way? I think they are two different structures and have different meanings.
I know there is zeugma, but I don't think this exercise can be regarded as a good example of zeugma. Maybe the writer just wanted to test these two structures and made an unnatural sentence.
Thank you in advance.

 

[emsr2d2]

Please provide the source and author of the book/article in which you found this exercise. It's a requirement of the forum due to copyright laws.

 

[Rover_KE]

Also asked and answered here.

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