razor-edge

n (also ,razor's `edge) (fig 比喻) 1 sharp line of division 明显的分界线: a razor-edge of difference between genius and madness 天才和疯狂之截然不同. 2 (idm 习语) on a razor-edge/razor's edge in a dangerous or critical situation 处於危险的境地; 处於紧要关头: Since he escaped from gaol, Tom has been living on a razor's edge, terrified of recapture. 汤姆越狱後, 时时如惊弓之鸟, 生怕再次被捕.

ravine, raving, ravings, ravioli, ravish, ravishing, ravishingly, raw, raw material, raw-boned, rawhide, rawness, ray, ray (also re), rayon, raze, raze (also rase), razor, razor-back, razor-blade, razor-sharp, razz, razzle, razzmatazz, RC, RCM, RD, re, re-, re-count, re-create, re-creation, re-echo, re-educate, re-education, re-elect, re-election, re-enter, re-entry, re-examination,