That is or that are

English as a Second Language English Vocabulary, Grammar and Idioms
1

Please suggest me which one of the following sentences is correct and why.
Also, can which replace that in these sentences?

Attached are the documents with a and b pages that are to be tested.

or

Attached are the documents with a and b pages that is to be tested

2

Please suggest which … do not add ‘me’.

What is being tested? The documents or just the pages? It is unclear.

Either way ‘documents’ (plural) or ‘pages’ (plural) require ‘are’ (plural).
You can use ‘which’ here.

3

Thanks for the correction.
The attached document has few pages and those pages need to be tested and not the document.

Can I use ‘those’ instead of ‘that’ in the sentence below?

Attached are the documents with a and b pages that are to be tested.

4

I would say:
Attached are the documents which include pages a and b. These are the pages which are to be tested.

5

Beeesneees,
‘Attached are the documents which include a and b pages which require testing.
Is this sentence OK?
Thanks.’

6

I would not use it. It is ambiguous. That is why I suggested two sentences.