老鼠过街，人人喊打

老鼠過街，人人喊打
lǎoshǔguòjiē,rénrénhǎndǎ
  1. lit. when a rat crosses the street, people chase it down (idiom)
  2. fig. everyone detests a lowlife

CEDICT

Entry Composition

1 老鼠 lǎoshǔ
  1. (archaic dialectal, Guilin Mandarin) bat (animal)
  2. (countable) mouse and rat in general (Classifier: 隻／只 m c h)
  3. bat (animal)
  4. cunning, deceitful person
  5. mouse and rat in general (Classifier: 隻／只 m c h)

classifier: 隻
2 过街 guòjiē to cross the street
3 人人 rénrén
  1. everyone
  2. every person
4 喊 hǎn
  1. to yell
  2. to shout
  3. to call out for (a person)
5 打 dǎ
  1. a semantically light, transitive verb that is combined with various grammatical objects to form compound verbs and verb-object phrases with a diverse range of meanings (e.g. 打伞 dǎsǎn "to hold an umbrella", 打电话 dǎdiànhuà "to make a phone call", 打针 dǎzhēn "to get an injection", 打手套 dǎshǒutào "to knit gloves", 打气 dǎqì "to inflate")
  2. to hit; to strike
  3. to fight
  4. (coll.) from; since (as in 打那以后 dǎnàyǐhòu "since then")