Comparison of our results with those from Gao et al. (2018) and Souto et al. (2018) for the two stars in common. Top panel: comparison of elemental abundances of the subgiant star Y1844 (black, blue, and red triangles represent the results fromthis work, Gao et al. 2018, and Souto et al. 2018, respectively). Bottom panel: comparison of elemental abundances of the turn-off star Y1388 (black and blue rectangles represent the results from this work and Gao et al. 2018, respectively). The dashed lines represent the locations of mean elemental abundances from the corresponding studies.