Answer:
Sarah, Matt's wife, works as a business software developer.
Explanation:
The noun Sarah preceding the appositive Matt's wife provides sufficient identification on its own, so we have to use commas around the appositive.
These sentences are written incorrectly:
The, local market, has the freshest produce and meats in town. We don't need to use commas around the subject <em>local market</em>.
Takeko, a painting student offered to help with a sculpting demonstration.
We need to use commas around the appositive <em>a painting student</em>.
The store offers, many products, which can be personalized with your initials. No commas are needed.
