Wahey finally something traditional i can criticise constructivly. I like your illustration syle of cartoons. If you are aiming towards cartoons then this may not relate. Try and get rid of the outlines on your drawings, draw the outlines lightly and when you come to shading you can reach those lines. Things in real life don't have edges around them and this goes for the same in realistec drawings. With the two hands clasping the apple, try and get quite a strong light source so you can really get into shading and remove some of those outer lines. I like the fourth one, the pose is good for that style of character. Now maybe add detail and your off! When doing hair, use a rubber to create the shine hair gives and the lighter strands. Hope i've helped. Practice and looking at other people's work is key