This may be a duplicate. The first time did not appear to actually post, possibly due to the links which have been removed for this version… If you put your photos on Flickr, it will be easier to refer to them with links.
Not awesome, but not bad.
I suspect you have the 55-200 mm lens, not a 55-20 mm one.
So. Mostly the usual stuff. Watch your backgrounds, stuff creeps in. Faster glass, wide open, would let you blur the background more which might help in some cases. Pay more attention to light, the eye goes to bright and in-focus.
A bright half background like img_6150.jpg has will draw the eye to the background. Try cropping it at the edge of the barn. See what you think. With light like the girl is in, popping a flash would add catch light to the eyes. That might be good, or it might reflect too much off her glasses. Next time, set a low power flash pop for a shot or two to see the effect.
With img_5454.jpg did you try standing in the bright area behind them and have them just turn around where they were standing? How did that work? I think it might work better. Again, with the way the photo was taken, I would expect a low power flash pop to light their eyes.
The camera’s pop-up flash will probably only work to 1/200th or so. To get a faster shutter speed, you need High Speed Sync, which is available with a Canon flash in the hot shoe.
In 5 girls, a low power flash would light their eye sockets and give catch lights, which would make them look better. Also, since a photo is two dimensional, a woman with shoulders square to the camera usually does not look as good as if one shoulder is closer than the other. Check out other people’s wedding photos on-line to see what you like, then try to remember those poses when taking your photos. If memory is not good, print some or add them to your phone so you can carry a reminder. The middle woman is doing a good job of channelling Taylor Swift, but she has a bridge support tower growing out of her head. It helps that it is in the fog and not sharp, but it would be even better if it were off to the side of them. The bridge deck cuts through behind them, also better to avoid that if you can by being a bit higher or lower when taking the shot.
That’s enough for now. Others may chime in, too. You are doing fine. Keep going.