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
573.答案是D;此处作children的定语，children与weigh是主动关系，故选weighing。
574.答案是D;此题to be repaired作定语表示将来。
