Please don't say obscene things in front of the children.
Tips
usage
Typical verbs: 说 / 讲下流话 (to say / tell dirty things). The 下流 part is the value judgment — 下流 ('low-flowing') means morally base, sleazy, vulgar; pair it with 话 (speech) and you get specifically obscene speech, not just rude or angry words.
