する
する · suru · JLPT N5 · verb-suru
to do
suru sounds like sure — Sure, I'll do it: suru = to do
Say sure quickly and you get suru, the all-purpose verb for doing. It also turns nouns into verbs: benkyou (study) + suru = to study. The same do stretches to putting on small items, as in nekutai o suru, to do up a necktie.