Finally, I had some time to put them all together.
Those are sketches from Drawing for Animators class at CCA.
I struggled a lot at the very beginning with forces, weight and directions of lines. Things got better with a lot of input from my teacher Ed Gutierrez and also from couple of books, Force: Dynamic Life Drawing for Animators, Second Edition by Michael D. and Drawn to Life: 20 Golden Years of Disney Master Classes: Volume 1: The Walt Stanchfield Lectures by Walt Stanchfield and Don Hahn. Those books are priceless.
As for my favorite sketch artist, I would choose Dave Pimentel. As Dave says: “Life is short – do a sketch!”