Practice sesh

You captured the shadows and rendered the poses quite clearly, though I would suggest creating more benchmarks to help with capturing proportion before you start sketching (and maybe it would help if you gave yourself more space with a larger sketch). For example, I like to make small marks just to note where a model's head, chest, hips, knees, and feet roughly are before I even start sketching the outline, which helps me keep the proportions more in line. The pose on the right has great capture of form!

細部からでは無く、全体やシルエットから描き始めましょう
頭、胴体、骨盤等大きくわかりやすいものを、丸や立方体、筒等の単純な形で下書きを描き、左右のバランスを何度も確認しながら描いてみましょう
もう少し大きく描いた方が描きやすいかもしれません
頑張ってね