A group of people standing around smiling, and in the background are more people and handmade signs.
A group of people are standing around with smiles are their faces, and in the background are more people and handmade signs.
Smiling is a paraphrase of smiles are their faces.
Smiling is a paraphrase of smiles are their faces.
"Smiles are their faces" is a rephrasing of "smiling"