Welcome to TPF!
They're a good start, but I can see a few areas for improvement. In the first one (For future reference, providing C&C is much easier if the images are numbered) Her eyes are very dark; some fill light in the form of either a low-powered speedlight or reflector would have really helped bring them to life and provide a nice catchlight. As well, the image needs to be straightened, and if you can, open up the right side where you've cropped some of her dress away. Like all portraiture, details are the killer; two seconds with a brush would have helped her hair greatly and when you're using grass, leaves, etc, watch their hands and feet. In this case, she looks like her hands have been amputated.
in #2, you've captured a great expression, but missed focus. The hem of her dress is in sharp focus, and her face is soft. ALWAYS know where your camera is focusing. For all types of portraiture, I recommend using a single focusing point and placing that where you want it, and of course, ensure you have an aperture which will provide sufficient DoF to render the face and other critical areas sharp. Again, her eyes are dark, and fill light would have helped, and would also have reduced the dynamic range and possibly prevented the blown/nearly blown highlights on the sneakers.
Just my $00.02 worth - your mileage may vary.
~John