איך אומרים באנגלית "על מי אתה עובד"?

who are you kidding?

?whom are you kidding
(who is someone kidding)
?who do you think you're kidding
**************
(are you kidding? (me
?do you think i was born yesterday
?don't fuck with me! /are you fucking with me
?are you trying to pull a fast one on me
?are you trying to do a snow job on me