I don't like the trees much, they look too artificial, and there's not much going on - just two random people standing idly. There are two many outlines and unnecessary lines, you should fix that. Also, the grass looks too flat, especially around the stone path that leads out of the block. The shadow on the left side from the shelter is different to the one on the right, that should be consistent. The building is alright, except for the lines I mentioned earlier.