Tour guides wearing traditional Chinese dress practice smiling by biting chopsticks at Qingming Grand-River Park in Kaifeng, central China's Henan Province on March 2, 2017, aiming to provide better service for visitors. (Photo by IPA Asia via ZUMA Wire)

Souvenirs seller smiles during the street market of the “2021 Agrorus” international agricultural fair at the Expoforum exhibition centre in St. Petersburg, Russia, 02 September 2021. The Exhibition opens for visitors until 05 September 2021. (Photo by Anatoly Maltsev/EPA/EFE)

These girls are all smiles as they celebrate surviving A-level results day in Birmingham, England on August 15, 2019. The A Level is a subject-based qualification conferred as part of the General Certificate of Education, as well as a school leaving qualification offered by the educational bodies in the United Kingdom. (Photo by SnapperSK/SnapperMS)

Nepalese Hindu devotees take part in a bathing ritual on the last day of the month-long Swasthani Festival in the Hanumante River at Bhaktapur on the outskirts of Kathmandu on February 22, 2016. Devotees mark the Swasthani Festival with fasting, and with women in particular undertaking rituals in the hope of a prosperous life for her family and conjugal happiness. (Photo by Prakash Mathema/AFP Photo)

A Hindu devotee bathes in the Shali River during the Swasthani Brata Katha festival, marked with auspicious bathing in water bodies hoping for a prosperous life and conjugal happiness, on the outskirts of Kathmandu on January 28, 2021. (Photo by Prakash Mathema/AFP Photo)

Stanford golfer Rose Shang smiles towards her teammates after winning the NCAA college women's golf championship at Grayhawk Golf Club, Monday, May 22, 2023, in Scottsdale, Ariz. (Photo by Matt York/AP Photo)

Visitors to West Midlands Safari Park in Bewdley, UK on October 17, 2023 are enjoying the bright October sunshine ahead of the storms to come. A curious giraffe meets eye to eye with a car full of happy visitors while licking the car windscreen with his long tongue. (Photo by Lee Hudson/Alamy Live News)

A Maasai woman smiles as Camilla, Duchess of Cornwall is presented with a traditional Maasai necklace as Prince Charles, Prince of Wales looks on during a visit to Majengo Maasai Boma on November 9, 2011 in Arusha, Tanzania. (Photo by Chris Jackson/Getty Images)