There is a great article that the Journal of Accountancy published which has an Exhibit of 2 circle diagrams that they use to demonstrate the relationship between RE professional time and material participation time as well as the 7 tests to meet material participation. 

The Co-owners desire to acquire, hold, maintain, keep in repair, rent and/or sell or exchange, as tenants-in-common (co-owners), that certain real property more fully described in Exhibit "A" attached hereto and incorporated herein by this reference (the "Property").