back at it

back at it (again)

Having resumed doing something, often something negative or unpleasant. A: "Do you hear arguing?" B: "Ugh, those two must be back at it again." I tried to stop biting my nails, but I'm back at it already.
See also: back
Farlex Dictionary of Idioms.

back at it (again)

doing something again. (Usually said in criticism.) I thought you stopped smoking, but I see you are back at it again.
See also: back
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • a bird in hand
  • a bird in the hand
  • (there's) no fear of (something)
  • a fast talker
  • a/the feel of (something)
  • (I) wouldn't (do something) if I were you
  • (have) got something going (with someone)
  • (you've) got to get up pretty early in the morning to (do something)
  • a straw will show which way the wind blows
  • a ghost at the feast