sentence: Smiles usually show happiness.
sentences_before: A 'smile' is a face made by flexing the muscles near both ends of the mouth. The neuropsychophysiological construction of the human smile.
sentences_after: A smile can be natural or fake. However, smiling can be different with animals. When smiling, the teeth shows, but sometimes animals do this when they are threatening. When chimpanzees show their teeth, it can also be a sign of fear.
concept_name: smile
headings: Smile
categories: Non-verbal communication