信口開河 (seon3 hau2 hoi1 ho4) — speak freely like a flowing river in Cantonese
seon˗₃信hauˊ²口hoiˉ¹開hoˎ₄河简 信口开河
Mandarin Pinyin: xin1 kou3 kai1 he2
Meaning of 信口開河
nounspeak freely like a flowing river
nounhave a loose tongue; idle talk; speak off the top of one's head