The two sentences that use commas in a way that is considered contested usage are:
- "We are passing through New Orleans, Louisiana right before we stop in Houston, Texas."
- "Faith, Millie's best friend from summer camp, is coming to visit in a few weeks."
The first sentence can be argued for or against the use of the second comma after "Louisiana," as there's a debate about the necessity of including geographic commas in non-restrictive phrases. The second sentence has a similar contest around the use of commas for non-restrictive appositives, though it's more widely accepted here.