Answer :
The sentence that correctly uses commas to create a compound sentence is: "The Library of Congress houses over 147 million items, and it is the largest library in the world." The comma comes before the conjunction 'and' and connects two independent clauses to make a compound sentence, while preventing run-on sentences and comma splices.
The correct sentence that uses commas to create a compound sentence is: "The Library of Congress houses over 147 million items, and it is the largest library in the world." A compound sentence is made up of two independent clauses connected by a conjunction, and a comma is usually required before the conjunction. In this case, 'The Library of Congress houses over 147 million items' and 'it is the largest library in the world' are the two independent clauses, and 'and' is the conjunction connecting them.
It is important to place the comma before the conjunction in a compound sentence, not after, as seen in the incorrect sentence: "The Library of Congress houses over 147 million items and, it is the largest library in the world." Also, omitting the comma completely as in "The Library of Congress houses over 147 million items and it is the largest library in the world" often leads to a run-on sentence, which is grammatically incorrect.
Finally, using a comma without a conjunction as in "The Library of Congress houses over 147 million items, it is the largest library in the world" creates a comma splice, which is another type of grammatical error.
The last sentence is correct and shows the use of a comma to create a compound sentence.
