Left panel: ALFOSC spectra from 2014 covering the [O i] 6300 line. The strong lines at −90 and +90 km s^-1 (solid) are from RW Aur A, while the single-emission component at zero velocity (dashed) is from RW Aur B. Right panel: high-resolution spectra of the same region. The dashed curve shows the [O i] profile from both RW Aur A and B in 2014, where the central peak belongs to RW Aur B, and the red-shifted sharp peak at +90 km s^-1 belongs to RW Aur A. The blue-shifted emission is shallow. Numerous narrow telluric absorption components and photospheric lines from component B are present. The solid curve in the right panel shows the [O i] profile in 1996, with the central peak at zero velocity and two peaks at −140 and +140 km s^-1. The forbidden lines are much stronger in the faint than in the bright state.