Two rows: front row 6 and back row 6.
Third platoon: 4 people in each platoon.
Four rows (suitable for gathering into small squares): three people in each row.
Triangle: the first row 1 person, the second row with 3 people, the third row with 4 people and the last row with 4 people.
Semicircular or circular
You can stand on your knees ~