First shot just doesn't work on any level Scoff, soz! The fountain would have made a great backdrop to that group though, assuming there was room to do it.
Shot 2. Oh dear! This is the happiest day of their lives and they look like they're standing there wondering what the photographer was doing, which they probably were. People left to their own devices will stand in front of the camera and line up like stumps, which is what has happened here. What was needed here was some input from YOU and advice on how to pose for the shot. If people don't get that they feel very vunerable and awkward and it really shows in this shot. Also you need to be outgoing and chatty and keep people smiling which would also have made a huge difference. There's nothing technically wrong with the shot at all, and you've chosen a decent background, but as I've said many times, the photography is almost incidental when doing weddings, you're being called on to exercise skill in posing and interplay with your subjects which you have no experience of, and that's the biggest hurdle to overcome for the newbie wedding photographer. You've also faced the couple into the sun in this shot which is why they're squinting uncomfortably
Shots 3 and 4 look far too squeezed into the frame, and the expressions are awful. You have to make sure that when you press that shutter button you have their full attention, and they're smiling.......... if they aren't, you have to make them do it!
The last shot - Bingo! - it's an absolute corker and they look like they're getting married and are actually both happy about it.
Nothing there to reproach yourself for Scoff, and let's face it, we're going to be more critical here than most people. The thing is to learn from this first wedding job, but the biggest problem with weddings isn't the actual photography, it's managing often large groups of people and getting your job done at the same time, and that really comes with experience.