Question

add or remove commas, if necessary, until the sentence has correct punctuation.
ryan howard updates his blog every day unless his favorite tv show is on.

Explanation:

The sentence contains a dependent clause ("unless his favorite TV show is on") that follows an independent clause ("Ryan Howard updates his blog every day"). When a dependent clause comes after an independent clause with a subordinating conjunction like "unless", no comma is needed to separate them. The proposed comma would incorrectly split the clauses.

Answer:

Remove the comma; the correct sentence is: Ryan Howard updates his blog every day unless his favorite TV show is on.