Respective. "They went to their respective homes." The adjective here (if an adjective is thought necessary) should be several. In the adverbial form the word is properly used in the sentence following: John and James are bright and dull, respectively. That is, John is bright and James dull.
Responsible. "The bad weather is responsible for much sickness." "His intemperance was responsible for his crime." Responsibility is not an attribute of anything but human beings, and few of these can respond, in damages or otherwise. Responsible is nearly synonymous with accountable and answerable, which, also, are frequently misused.
Restive for Restless. These words have directly contrary meanings; the dictionaries' disallowance of their identity would be something to be thankful for, but that is a dream.
Retire for Go to Bed. English of the "genteel" sort. See Genteel.
Rev. for The Rev. "Rev. Dr. Smith."
Reverence for Revere.
Ride for Drive. On horseback one does drive, and in a vehicle one does ride, but a distinction is needed here, as in England; so, here as there, we may profitably make it, riding in the saddle and driving in the carriage.
Roomer for Lodger. See Bedder and Mealer—if you can find them.
Round for About. "They stood round." See Around.
Ruination for Ruin. Questionably derived and problematically needful.