Complex sentence: The term may refer specifically to a Tridentine Mass said by a priest with the assistance of one or more servers, instead of a deacon and subdeacon and other ministers, and was the most common form of Mass before 1969.
Split into simpler sentences: The term may refer specifically to a Tridentine Mass said by a priest with the assistance of one or more servers, instead of a deacon and subdeacon and other ministers. Low Mass was the most common form of Mass before 1969.