想當然

想当然
xiǎngdāngrán
to take sth as given; to make assumptions

CEDICT

to take something for granted

Wiktionary

推測、猜想必定是如此。

重編國語辭典

Entry Composition

1 想 xiǎng
  1. to think (about)
  2. to think of; to devise
  3. to think (that); to believe (that)
  4. to desire; to want (to)
  5. to miss (feel wistful about the absence of)
2 當然 dāngrán
  1. only natural
  2. as it should be
  3. certainly
  4. of course
  5. without doubt

Containing this entry

想當然爾 xiǎngdāngráněr
  1. to take sth as given
  2. to assume
  3. as one would expect
  4. naturally
想當然耳 xiǎngdāngráněr variant of 想當然爾 xiǎngdāngráněr