Question

read this sentence.
all cars that are not registered will be towed to the nearest impound lot.
identify the relative clause, whether it is essential to the meaning of the sentence, and if it requires commas.
the clause is \that are not registered.\
it is non - essential.
it does require a comma.
the clause is \to the nearest impound lot.\
it is essential.
it does not require a comma.
the clause is \that are not registered.\
it is essential.
it does not require a comma.
the clause is \to the nearest impound lot.\
it is non - essential.
it does require a comma.

Explanation:

A relative clause modifies a noun. In "All cars that are not registered will be towed to the nearest impound lot", "that are not registered" modifies "cars". An essential (restrictive) relative clause is needed to identify the specific noun (here, which cars - the unregistered ones). Non - essential clauses (using "which") give extra info and are set off by commas. Since "that" is used for essential clauses and no commas are around "that are not registered", it is essential and no commas are required.

Answer:

The clause is “that are not registered.” It is essential. It does not require a comma.