Russians, who apparently don’t smile as effortlessly as other Europeans, are being taught to greet tourists arriving for the 2018 FIFA World Cup, which starts on Thursday, with a cheeky grin.

According to The Atlantic, a Russian proverb, which says, "laughing for no reason is a sign of stupidity," may be the reason for the Russians' glum demeanor. Yet on the eve of one of the biggest sporting events in the world, Russia, which will welcome 1.5 million foreign tourists, is finding reasons to flash their pearly whites.

Workers at companies like FIFA, Russian Railways, and Moscow Metro are being trained to seem affable. "Russian train conductors are being taught how to smile at foreigners," says one report. Russia may have reasons to be happy tomorrow, however, since they’ll have the home team advantage when they take on Saudi Arabia in the opening match.

“We want to attract more foreign tourists; it’s good for our economy,” Evgenia Zaborskaya, one of the trainers said. “We just want to show the beauty of Moscow and the Moscow underground.”

Training includes laughter yoga classes in which workers attempt to appear upbeat, friendly and silly.

“It’s strange for a person to walk down the street and smile. It looks alien and suspicious,” said Yulia Melamed, one of the workers undergoing training, who reported being stopped once by a police officer for grinning. “It is strange for a person to walk on the street and smile. It looked alien and suspicious,” the officer told Melamed.

According to a 2017 survey, the countries with the happiest workers include, Denmark, Switzerland, Canada, New Zealand and Australia, where workers rated their employment situation an average of 7.4 out of 10. Russians, however, only rated theirs a 5.8. Countries like Iran, China, Nepal, Cameroon and South Africa all rated their workplace between a 4.4 and a 5.2.

Elnara Mustafin, a Russian psychologist, says that workers’ attitudes can have a negative impact on tourists. “When other people come to Russia, they think Russians are not friendly. We need to teach them how to smile. We need to change their attitude.”

One company in Russia with a history of teaching workers to smile is McDonald’s. In 1990, when the company opened its first franchise in Russia, workers had to be trained to be polite and smile. On a 2016 episode of the Invisibilia podcast, Yuri Chekalin, a former McDonald’s employee, noted how the training affected the consumer experience.

“Everywhere else you go it was just gloomy and dark and dirty and there were troubles, stress, and you come to McDonalds and it’s–everybody’s always happy and you see smiles. You can’t make any mistakes and you can stay there as long as you want. Nobody's going to kick you out. And so it was just a great place to hang out. People really felt they could just relax and be themselves.”

RELATED: 21 Airports You'll Actually Be Happy About Having A Layover In

According to the 2016 Smiling Report, compiled by Better Business World Wide, which gathers customer service data from evaluations of different industries, Ireland scored the highest with 100%, while Spain and Switzerland scored 97%, and Greece 94%. At the bottom of the list, Hong Kong scored 48%, Macau 53% and Croatia 59%.