For S, from KWER, perna- transitive "to turn", to be used in a wider sense (e.g. to turn a Wheel, to turn one's coat, the Sun turns the trolls into stone, to turn English into Elvish). I looked at the Q Word quer- http://eldamo.org/content/words/word-2748402405.html and I would have liked to also make an intrasitive verb, but as Ekin pointed out, a simple per- would be homonymous with that for "to halve". Alternatively, perna- could be both transitive and intransitive.