可行
kěxíng · HSK 7
feasible
可行 = 可 (can) + 行 (go/do) = can-be-done, i.e. doable
可 means can or able and 行 means to go or to walk, by extension to do. Stick them together and something that can be done is feasible. The same 行 shows up in 行得通, meaning workable.
可 — mouth 口 + breath marker 丁 (modified)
可 originally depicted a mouth (口) with a curved stroke suggesting exhaled breath or speech, conveying approval or assent. From this came the meaning 'to permit' or 'can,' as granting permission was expressed verbally. Today it broadly means 'may,' 'can,' or 'approve.'
行 — crossroads pictograph (left 彳 + right 亍)
行 originally pictured a four-way crossroads in oracle bone script, with two paths meeting. From 'road' it extended to 'walk, go, travel,' and then to 'a row, line' or 'business firm' (read háng). The two halves 彳 and 亍 are the split sides of that ancient crossroads.