Good job! Drawing animals is really hard, but these turned out good! For the shark, I would say you could do a lot more foreshortening like in the picture, don't be afraid to have those ellipses overlap. The goat and lion look good and the main thing I'm seeing is that, especially in the lion, some of the forms are almost too simplified, like the lion torso. Instead of one big shape, remember animals have a ribcage and pelvis that tilt and work independently just like we do. The lion legs as well I would've separated into shapes of the top part of the arm/leg, the elbow/ankle, and the bottom part as three separate shapes, like when you did the goat.

these look good! My biggest critique would be to draw through the forms, that helps tremendously with finding the mass and form and also helps to guide your cross contours, which you could also do more of