Solid work.
I would say the first one is the best in my opinion. I would consider the rule of thirds in that picture though, it would make it much more interesting to have the fountain bottom right with the lit structure & have negative space left of it.
The bike picture and person ones don't really do it for me. More snap shots than photographs if you know what I mean. You did use leading lines and DOF well with the tire though. The person picture is played, think about getting it from a different angle maybe wide angle below.
Hope that helps a little.