(pos:名詞)
<explanation>
yue:#警告 對方並要求改善、否則就會作進一步行動嘅#信件（量詞：封）
eng:warning letter
<eg>
yue:佢上網講錯嘢，公司冇出警告信直接炒咗佢。 (keoi5 soeng5 mong5 gong2 co3 je5, gung1 si1 mou5 ceot1 ging2 gou3 seon3 zik6 zip3 caau2 zo2 keoi5.)
eng:He said something politically incorrect online, and the company fired him without issuing a warning letter.