Base Offering Circular – Multifamily 66 Corrected Certificate Factor......  With respect to any Ginnie Mae Multifamily Certificate for which an incorrect Certificate Factor is reported, a corrected certificate factor agreed to by the related Ginnie Mae Issuer and the Trustee by 12:00 noon Eastern time on the second Business Day preceding a Distribution Date. Co-Sponsor ............................. With respect to a Series, the Person, identified in the Sponsor Agreement, with whom the Sponsor has entered into an agreement pursuant to which the Co-Sponsor at its election may distribute certain of the Securities. Co-Trust Counsel..................... With respect to a Series, a law firm, identified in the Sponsor Agreement, whom the Sponsor has retained to perform legal work assisting Trust Counsel in the discharge of Trust Counsel’s responsibilities. Current Interest Class...............  A Class that bears interest and is not an Accrual or Partial Accrual Class. Current Interest Security...........  A Security of a Current Interest Class. Cut-off Date ...........................  With respect to any Series, the date specified in the related Offering Circular Supplement for such Series. CUSIP Number .......................  A unique nine-character designation assigned by the CUSIP Service Bureau to each Class. Delay Class ............................  A Class for which there is a delay between the end of its Accrual Period and the related Distribution Date.   Descending Rate Class..............  A Class that has predetermined Interest Rates that decrease one or more times on dates determined before issuance. Differential Class .....................  A Class with Interest Rates that are equal to the difference between two specified indices.