From an e-mail I sent yesterday: “[I] had to stay in the hotel while everyone else… sightsaw? sightseed? sheesh, what is the past tense?… Merriam-Webster says ‘sightsaw,’ but that sounds awful to me…” My correspondent agreed it sounded wrong, and said he’d say “went sightseeing,” which I realized immediately was the past tense people actually use. But what an odd verb! Does anybody find sightsaw normal and use it naturally? And does anybody know if there are other verbs whose regular past tense is on the fringe of acceptability?