Gas and star formation rate surface densities of 4C 41.17 (red diamond), PKS 0529−549 (blue dot), and several comparison samples: Giant molecular clouds in the Milky Way (Evans et al. 2014), local starburst galaxies (Kennicutt 1998a), star-forming galaxies at z = 1−2 (Tacconi et al. 2008; Valentino et al. 2018, 2020), and submillimeter galaxies (Bothwell et al. 2010). The solid purple and blue lines indicate the sequences for typical main-sequence and starburst galaxies of Daddi et al. (2010).