could (do something) in (one's) sleep

Is able to do something with very little or no difficulty, or complete or accomplish something in a relaxed, carefree, or effortless manner. It took me a little while to get used to this job, but now I could do it in my sleep! You should ask Johnny for help—he could do this level of math in his sleep.

someone could do something in their sleep

someone could do or accomplish something with no effort or conscious thought. informal

See also: could, sleep, someone, something

Farlex Partner Idioms Dictionary

See also:

able to do (something) with (one's) eyes closed
able to do with eyes closed
able to do blindfolded
able to (do something) blindfolded
able to (do something) with (one's) eyes closed
able to do (something) standing on (one's) head
a/the feel of (something)
(I) wouldn't (do something) if I were you
a straw will show which way the wind blows
a crack at (someone or something)

词组	could (do something) in (one's) sleep
释义	could (do something) in (one's) sleep could (do something) in (one's) sleep Is able to do something with very little or no difficulty, or complete or accomplish something in a relaxed, carefree, or effortless manner. It took me a little while to get used to this job, but now I could do it in my sleep! You should ask Johnny for help—he could do this level of math in his sleep. See also: could, sleep Farlex Dictionary of Idioms. someone could do something in their sleep someone could do or accomplish something with no effort or conscious thought. informal See also: could, sleep, someone, something Farlex Partner Idioms Dictionary See also: able to do (something) with (one's) eyes closed able to do with eyes closed able to do blindfolded able to (do something) blindfolded able to (do something) with (one's) eyes closed able to do (something) standing on (one's) head a/the feel of (something) (I) wouldn't (do something) if I were you a straw will show which way the wind blows a crack at (someone or something)
随便看	fungus fungus-face funk funked out funking half-naked half of it half-pint half seas over half-shaved halfsies half-sprung half-stewed half term half the battle half the fun of (something) half the fun, trouble, etc. of something half the time half the trouble of (something) half the truth is often a whole lie half the world knows not how the other half lives half under half-under half up the pole halfway