When it comes to choosing clothes for a wedding party, there are various options for girls to look beautiful. The choice of attire will depend on the formality of the event, the theme (if any), personal style, and the season. Here are some suggestions:

1. Formal/Black-Tie Wedding: A long evening gown or a sophisticated cocktail dress would be appropriate. Opt for elegant fabrics like silk, chiffon, or satin in colors like black, navy, or jewel tones.
2. Semi-Formal Wedding: A knee-length or tea-length dress can work well. Choose a dress in a flattering silhouette, such as an A-line or fit-and-flare style. Consider fabrics like lace or tulle, and opt for softer colors like pastels or neutrals.