After returning to camp, Dr. Alfons and the explorers plan their route for the next day of exploration
After returning to camp, Dr. Alfons and the explorers plan their route for the next day of exploration  Is this set of an introductory clause, phrase, or Set off non-restrictive modifier modifying words that could be removed without loss of meaning Separates coordinates, adjectives adjectives that independently, modify the same noun Separate items in a series Join two main clauses