Question

fix any punctuation or capitalization errors below. click \submit answer\ if there are none.
river butterfly and his tap dance teacher went door to door this morning, singing their favorite songs to their neighbors.

Explanation:

The sentence has a punctuation error: the comma after "morning" incorrectly separates the main clause from the participial phrase that modifies the subject's action. This comma should be removed.

Answer:

River Butterfly and his tap dance teacher went door to door this morning singing their favorite songs to their neighbors.