A military instructor of the U.S. Army instructs Ukrainian servicemen during the multinational drills "Rapid Trident 2020" at the International Peacekeeping and Security Center near Lviv, Ukraine September 19, 2020. REUTERS/Gleb Garanich

A military instructor of the U.S. Army encourages Ukrainian servicemen during the multinational drills "Rapid Trident 2020" at the International Peacekeeping and Security Center near Lviv, Ukraine September 19, 2020. REUTERS/Gleb Garanich

A military instructor of the U.S. Army is seen near Ukrainian servicemen during the multinational drills "Rapid Trident 2020" at the International Peacekeeping and Security Center near Lviv, Ukraine September 19, 2020. REUTERS/Gleb Garanich

An instructor wearing a face shield helps a woman exercise inside a health centre amidst the coronavirus disease (COVID-19) outbreak in Ahmedabad, India, September 7, 2020. REUTERS/Amit Dave

An instructor shows a monitoring system that can minimize interaction between healthcare workers and patients to prevent the spread of coronavirus disease (COVID-19) at a "Nurse summer camp" event at Taipei Medical University Hospital in Taipei, Taiwan, August 21, 2020. REUTERS/Ann Wang

An instructor of the training center explains the structure of an EUV machine to the media at ASML Holding, in Tainan, Taiwan August 20, 2020. REUTERS/Ann Wang

Kids listen to their instructor at a volleyball camp on the beach amid a heatwave and the outbreak of the coronavirus disease (COVID-19) in Del Mar, California, U.S., August 19, 2020. REUTERS/Mike Blake

Britain's Prime Minister Boris Johnson talks to an instructor as he visits Premier Education Summer Camp at Sacred Heart of Mary Girls' School, as the coronavirus disease (COVID-19) outbreak continues, in Upminster, London, Britain August 10, 2020. Lucy Young/Pool via REUTERS

Britain's Prime Minister Boris Johnson greets an instructor with an elbow bump as he visits Premier Education Summer Camp at Sacred Heart of Mary Girls' School, as the coronavirus disease (COVID-19) outbreak continues, in Upminster, London, Britain August 10, 2020. Lucy Young/Pool via REUTERS

An instructor looks on (R) as a U.S. Military Academy (USMA) cadet throws a live hand grenade during tactical and physical training activities as part of Cadet Summer Training at West Point, New York, U.S., August 7, 2020. REUTERS/Mike Segar

Military instructors look on as a U.S. Military Academy (USMA) cadet emerges from the water confidence course, during tactical and physical training activities as part of Cadet Summer Training at West Point, New York, U.S., August 7, 2020. REUTERS/Mike Segar

Lateif Dickerson, Director and Chief Instructor for the New Jersey Firearms Academy, poses at the academy in Jersey City, New Jersey, U.S., July 23, 2020. Picture taken July 23, 2020. REUTERS/Shannon Stapleton

Lateif Dickerson, Director and Chief Instructor for the New Jersey Firearms Academy, poses at the academy in Jersey City, New Jersey, U.S., July 23, 2020. Picture taken July 23, 2020. REUTERS/Shannon Stapleton

Lateif Dickerson, Director and Chief Instructor for the New Jersey Firearms Academy, poses at the academy in Jersey City, New Jersey, U.S., July 23, 2020. Picture taken July 23, 2020. REUTERS/Shannon Stapleton

Pictures, plaques and manuals are seen for Lateif Dickerson, Director and Chief Instructor for the New Jersey Firearms Academy, in Jersey City, New Jersey, U.S., July 23, 2020. Picture taken July 23, 2020. REUTERS/Shannon Stapleton

Lateif Dickerson, Director and Chief Instructor for the New Jersey Firearms Academy, speaks to a man at the academy in Jersey City, New Jersey, U.S., July 23, 2020. Picture taken July 23, 2020. REUTERS/Shannon Stapleton

Plaques are seen for Lateif Dickerson, Director and Chief Instructor for the New Jersey Firearms Academy, in Jersey City, New Jersey, U.S., July 23, 2020. Picture taken July 23, 2020. REUTERS/Shannon Stapleton

Customers learn yoga from an instructor at a changing room of public bathhouse "Daikoku-yu", amid the coronavirus disease (COVID-19) pandemic in Tokyo, Japan July 17, 2020. Picture taken July 17, 2020. REUTERS/Akira Tomoshige

Yoga instructors get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

A yoga instructor gets ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors perform yoga as they get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors are seen as they get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

A yoga instructor performs yoga as she gets ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors are seen as they get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors perform yoga as they get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

A yoga instructor performs yoga as she gets ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Yoga instructors perform yoga as they get ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

A yoga instructor performs yoga as she gets ready for reopening of MyBody Studios, following the coronavirus disease (COVID-19) outbreak, in East Boldon, near Sunderland Britain July 24, 2020. REUTERS/Lee Smith

Syrian refugee students and instructor, Yasine Hariri, use his invention that is a robot prototype that automatically dispenses sanitiser to avoid contact and combat the spread of the coronavirus disease (COVID-19) as a part of the camp's UNHCR-led Innovation Lab program, at the Zaatari refugee camp in the Jordanian city of Mafraq, near the border with Syria, July 14, 2020. Picture taken July 14, 2020. REUTERS/ Muhammad Hamed

Syrian refugee students and instructor, Yasine Hariri, use his invention that is a robot prototype that automatically dispenses sanitiser to avoid contact and combat the spread of the coronavirus disease (COVID-19) as a part of the camp's UNHCR-led Innovation Lab program, at the Zaatari refugee camp in the Jordanian city of Mafraq, near the border with Syria, July 14, 2020. Picture taken July 14, 2020. REUTERS/ Muhammad Hamed

Syrian refugee students and instructor, Yasine Hariri, use his invention that is a robot prototype that automatically dispenses sanitiser to avoid contact and combat the spread of the coronavirus disease (COVID-19) as a part of the camp's UNHCR-led Innovation Lab program, at the Zaatari refugee camp in the Jordanian city of Mafraq, near the border with Syria, July 14, 2020. Picture taken July 14, 2020. REUTERS/Muhammad Hamed

Syrian refugee lab instructors, train teenage students to create robots as part of the camp's UNHCR-led Innovation Lab program, at Al Zaatari refugee camp in the Jordanian city of Mafraq, near the border with Syria, July 14, 2020. Picture taken July 14, 2020. REUTERS/Muhammad Hamed

A boy wearing a protective face mask recites verses from Koran to his instructor during a Koran memorization class as Palestinians ease the coronavirus disease (COVID-19) restrictions, in a mosque in Gaza City June 25, 2020. REUTERS/Mohammed Salem

Yoga instructor Kay Ghajar leads an outdoor yoga class by LMNTS Outdoor Studio, in a dome to facilitate social distancing and proper protocols to prevent the spread of coronavirus disease (COVID-19), in Toronto, Ontario, Canada June 21, 2020. REUTERS/Carlos Osorio

Yoga instructor Kay Ghajar leads an outdoor yoga class by LMNTS Outdoor Studio, in a dome to facilitate social distancing and proper protocols to prevent the spread of coronavirus disease (COVID-19), in Toronto, Ontario, Canada June 21, 2020. REUTERS/Carlos Osorio

Yoga instructor Kay Ghajar leads an outdoor yoga class by LMNTS Outdoor Studio, in a dome to facilitate social distancing and proper protocols to prevent the spread of coronavirus disease (COVID-19), in Toronto, Ontario, Canada June 21, 2020. REUTERS/Carlos Osorio

Yoga instructor Kay Ghajar leads an outdoor yoga class by LMNTS Outdoor Studio, in a dome to facilitate social distancing and proper protocols to prevent the spread of coronavirus disease (COVID-19), in Toronto, Ontario, Canada June 21, 2020. REUTERS/Carlos Osorio

An instructor conducts a class at a gym that installed individual plastic pods to maintain social distancing, as the coronavirus disease (COVID-19) outbreak continues in Ciudad Juarez, Mexico June 17, 2020. Picture taken June 17, 2020. REUTERS/Jose Luis Gonzalez

An instructor conducts a class at a gym that installed individual plastic pods to maintain social distancing, as the coronavirus disease (COVID-19) outbreak continues in Ciudad Juarez, Mexico June 17, 2020. Picture taken June 17, 2020. REUTERS/Jose Luis Gonzalez

An instructor conducts a class at a gym that installed individual plastic pods to maintain social distancing, as the coronavirus disease (COVID-19) outbreak continues in Ciudad Juarez, Mexico June 17, 2020. Picture taken June 17, 2020. REUTERS/Jose Luis Gonzalez

An instructor conducts a class at a gym that installed individual plastic pods to maintain social distancing, as the coronavirus disease (COVID-19) outbreak continues in Ciudad Juarez, Mexico June 17, 2020. Picture taken June 17, 2020. REUTERS/Jose Luis Gonzalez

An instructor conducts a class at a gym that installed individual plastic pods to maintain social distancing, as the coronavirus disease (COVID-19) outbreak continues in Ciudad Juarez, Mexico June 17, 2020. Picture taken June 17, 2020. REUTERS/Jose Luis Gonzalez

Sports instructor Marina Cruz hugs Pilar Zanon as she tries to motivate her to do physical exercise at the Alas Foundation centre for women with intellectual disabilities amid the COVID-19 outbreak in Madrid, Spain, June 15, 2020. Picture taken June 15, 2020. REUTERS/Susana Vera

Sports instructor Marina Cruz leads a gym class where the students keep social distancing at the Alas Foundation centre for women with intellectual disabilities amid the COVID-19 outbreak in Madrid, Spain, June 15, 2020. Picture taken June 15, 2020. REUTERS/Susana Vera

Lifeguard 1 instructor Christopher Zang wears a mask as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

An instructor records participants ocean swim times as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang (R) organizes participants as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Participants are timed by Lifeguard 1 Instructor Christopher Zang during a beach run test as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang (R) organizes participants as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang (L) organizes participants as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang (R) organizes participants as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Participants and instructors wear masks on the beach as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Instructors gather participants on the beach as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang (R) organizes participants as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang watches over ocean swimmers as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for novel coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake

Lifeguard 1 instructor Christopher Zang directs arriving ocean swimmers as San Diego's Junior Lifeguard Program officially reopens with new protocols in place to comply with county health guidelines for coronavirus safety during the outbreak of COVID-19 in San Diego, California, U.S., June 15, 2020. REUTERS/Mike Blake