DEFINING and NON-DEFINING RELATIVE CLAUSES? [closed]

Which of the following sentences below is/are grammatical?

SENTENCE 1: This is the bread that you gave me, that is sold at ABC bakery.

SENTENCE 2: This is the bread that you gave me that is sold at ABC bakery.

SENTENCE 3: This is the bread that you gave me, which is sold at ABC bakery.

Non-defining relative clauses give additional information to your sentence. This information is not necessary to understand who or what is being referred to. We do need commas around non-defining relative clauses in a sentence.

Therefore, the third sentence is preferable.

This is the bread that you gave me, which is sold at ABC bakery.

You can remove the clause [which is sold at ABC bakery] and the sentence still makes sense.

However, defining relative clauses do not need commas. Here are some examples of defining relative clauses:

The lady who teaches me English is from Britain.

The English course which I have chosen lasts for 10 weeks.

The book that we are learning grammar from is really helpful.

You can find out more about relative clauses in this blog post: https://intrepidenglish.co.uk/relative-clauses/

Let me know if you have any questions and best of luck with your studies.

If the second clause is nonrestrictive, i.e. you didn't give me breads from multiple bakeries, it takes a comma, and #2 is faulted. Following the recommended practice of using "which" for nonrestrictive clauses, #3 is best.

If restrictive, i.e. multiple breads and bakeries, then #2 is correct.