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I wrote this sentence
In this paper, we aim to present an approach and a system to construct wrappers which are independent of the HTML structure of the page.
I know the difference of "which" and "that" as that is restrictive but which is not. However, in articles as I searched in Google I saw both usage.
Then I am confused if it is a restrictive or non-restrictive here, as I heard to avoid using which for restrictive clauses, and they may need a "the" article before the noun!?