最善

N1 親善 shinzen friendship N1 善良 zenryou goodness, excellence, virtue N1 善し悪し yoshiashi good or bad, merits or demerits, quality N2 最～ sai～ the most ~ N3 改善 kaizen improvement, betterment N3 最高 saikou highest, best, supreme N3 最終 saishuu final, last, closing N3 最中 saichuu in the middle of, during N3 最低 saitei lowest, worst, minimum

N3 最 sai, shu / motto.mo, tsuma utmost, most, extreme N1 善 zen / yo.i, i.i, yo.ku, yoshi.tosuru virtuous, good, goodness