蜀犬吠日

shǔquǎnfèirì

to be surprised at something common because of one's ignorance

Wiktionary

Homographs

蜀犬吠日 Shǔquǎnfèirì
  1. lit. Sichuan dogs bark at the sun (idiom); fig. a simpleton will marvel at even the most common things
  2. alludes to the Sichuan foggy weather where it's uncommon to see a sunny day

Entry Composition

=1 蜀 Shǔ
  1. short name for Sichuan 四川 Sìchuān province
  2. one of the Three Kingdoms 三國 Sānguó after the Han dynasty, also called 蜀漢 Shǔ Hàn, situated around what is now Sichuan province
=1 蜀 shǔ
  1. (historical dictionaries only) silkworm on hollyhock
  2. (obsolete on its own in Standard Chinese) alternative form of 蠋 (zhú, “caterpillar”)
  3. (～國) the name of a state in ancient China
  4. Sichuan (a province of China)
  5. alternative form of 蠋 (zhú, “caterpillar”)
  6. another name for Shu Han, one of Three Kingdoms
  7. silkworm on hollyhock
  8. the name of a state in ancient China
2 犬 quǎn
  1. (literary) dog
  2. Kangxi radical 94
3 吠 fèi to bark
=4 日 Rì abbr. for 日本 Rìběn, Japan
=4 日 rì
  1. sun
  2. day
  3. date, day of the month