念念不忘

niànniànbùwàng
to keep in mind constantly (idiom)

CEDICT

Entry Composition

=1 念 niàn variant of 念 niàn, to read aloud
=1 念 niàn
  1. to read
  2. to study (a subject)
  3. to attend (a school)
  4. to read aloud
  5. to miss (sb)
  6. idea
  7. remembrance
  8. twenty (banker's anti-fraud numeral corresponding to 廿 niàn)

classifier: 頓
=2 念 niàn variant of 念 niàn, to read aloud
=2 念 niàn
  1. to read
  2. to study (a subject)
  3. to attend (a school)
  4. to read aloud
  5. to miss (sb)
  6. idea
  7. remembrance
  8. twenty (banker's anti-fraud numeral corresponding to 廿 niàn)

classifier: 頓
3 不 bù
  1. no; not so
  2. (bound form) not; un-
4 忘 wàng
  1. to forget
  2. to overlook
  3. to neglect