Nice work! It's so cool that you're becoming an interpreter. I'm jealous of people who can speak another language well. Which language(s) are you studying? I'm loving the greyscale dragon/girl images! There's some nice storytelling going on.
You've done a good job on a cool and warm scenario skintones. I hope you don't mind, but I've done a piantover of one of the gals (I wrecked her face... I'm really sorry ). You have your light source, but you seem a bit uncertain about what it's doing. If you simplify, it gets easier. I've done it in the bridgeman type style, and a bit more complicated. The second also shows a bit of an outline of a shadow (in purple). I hope this helps!