Usage of lest how to use "lest"? I suppose it's somehow close either to "unless" or "not to", albeit I'm not sure if conditionals are allowed to be used as well, moreover, I guess, lest implies negative sense if there are positive sentences and vice versa. do not pull the lever, lest she's crumbled up by the saw(if she was captured by a maniac and her body was seized and stuck between a wall and the well-hung saw) if I hadn't picked the successive point of that agenda lest I had been impeached and deprived from social perks such as my own yacht and the most contemporary model of "Ford" cars, I wouldn't be inmate now. I called her immediately lest she would know about his yesterday's sins at the enjoying party if you had printed out those memos ,lest I had been suspended and not lost my high social status, I would've approved of your idea in state duma