Everyone in this class must hand in their ( his ) test paper within the given time.
Everyone in this class must hand in their ( his ) test paper within the given time.
班上每个人都必须在规定的时间内交上他们的试卷。
Everyone in this class must hand in their ( his ) test paper within the given time.
班上每个人都必须在规定的时间内交上他们的试卷。