Question

are both these sentence grammatically correct?

I brought the food he ate.
or
I brought the food that he ate.

can you also provide the rule or explanation ie. restrictive clause?

Answer 1

No 2. I brought the food that he ate.

A restrictive modifying clause (or essential clause) is an adjective clause that is essential to the meaning of a sentence because it limits the thing it refers to. The meaning of the sentence would change if the clause were deleted. Because restrictive clauses are essential, they are not set off by commas.

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