Line profiles of the emission lines detected in H1429−0028 on each of the specified knots A+B, C and D (grey boxes): CO(4 → 3) as solid black line; CS(10 → 9) as a dotted red line (scaled up by a factor of 2); and [CI 3P1→3P0] as dashed blue line (scaled up by a factor of 2). The bottom right panel compares the line profiles of the overall CO(2 → 1) (dashed line, scaled up by a factor of 2.5) and CO(4 → 3) (solid line) emission. Different spectral resolutions are considered (20 km s^-1 for CO(2 → 1), CO(4 → 3) and C i, and 40 km s^-1 for CS(10 → 9)). The y-axes have the same span in all panels, except the bottom right one. The x-axis range is −600 to 800 km s^-1 in all panels. The horizontal solid line indicates the zero-flux level. The background colour image is the CO(4 → 3) moment-0 map from Fig. 4.