偶ㄡˇǒu一ㄧyī為ㄨㄟˊwéi之ㄓzhī

  1. 偶然做一次。宋·歐陽修〈縱囚論〉：「若夫縱而來歸而赦之，可偶一為之耳。」

英to do sth once in a while (idiom)​, to do sth more as an exception than the rule