A dark-haired lady with a big smile is wearing a bright red scarf.
The dark-haired lady frowned and wore all black
The lady cannot have a big smile and also be frowning, and she cannot be wearing all black if she has a bright red scarf.
A person cannot be frowned and have a big smile at the same time
The lady can not have a big smile and frown at the same time. She can not wear all black if she is wearing a red scarf.