573.The traffic rule says young children under the age of four and ______ less than 40 pounds must be in a child safety seat.
A.being weighed
B.to weigh
C.weighed
D.weighing
574.Many buildings in the city need repairing,but the one ______ first is library.
A.repaired
B.being repaired
C.repairing
D.to be repaired