Have a feeling this is going to be moved to the "General Gallery" or somewhere...
Anyway, (These are just my opinions and aren't based on much in the way of "technicality")
1. One is okay, a tad boring maybe? The angle may have been better from the "opposite" angle looking away from the building. Makes for a more interesting background. (maybe...)
2. Is my favorite. Some of industrial kind of stuff kills it a bit (the roof unit, and the lights? on the columns) but I like the juxtaposition between the blooming tree and the kind of "dead' vibes the lighting gives.
(Unlabeled #3). I know its fun when playing around with exposures to make ghosts of yourself, but as a photograph it isn't really much of anything

nor is the composition very good
4. second favorite. It has the best lighting (for my tastes; although still pretty "dead" looking) and the timing and the angle are both good. Could have had some tighter framing on the skater. (ie. Zooming in closer to the window.)
Overall,
Not sure if it is just the look you are going for, but you definitely have a "sorrowful" vibe to your photos. Nothing is vibrant or very positive looking. Which isn't necessarily a bad thing, I just wasn't sure if that is what you were going for!
My 2 cents!
Cheers
Edit: (You also haven't selected whether your photos are okay to edit, otherwise I would demonstrate for a couple of my comments... )