1824. What character can be added to both of these characters to give other characters? 折_ -> _尺

Answer:

折  SETSU, o(ru), o(reru), ori - break, fold, yield, bend, occasion

尺  SHAKU - measure, length

Add 言:折+言 言+尺 

言  GEN, GON, i(u), koto - say, speech

誓  SEI, chika(u) - swear, pledge, vow

訳  YAKU, wake - translation, reason, meaning