subserves

"He promoted his clerk to office manager."

"He is a student of life."

"To help pay her tuition, the college student began to tutor high school students in calculus and physics."

"The mandatory for the game requires the players to keep the disc above the painted line. "

"She was carrying a heavy backpack to school. "

"Attendance at the meeting is required."

"Buying more servers would improve performance."

"My new cookbook is very useful for learning how to cook healthy meals. "

"Our program for today’s exercise class includes swimming and jogging."

"He is a student of life."

"The Communist Party has a policy of returning power to the workers."

"My parents are ensuring my younger sister gets to school on time every day. "