Question

 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

Answer

 D

解析：本题考查非谓语动词。根据句子结构：主语：the traffic rule；谓语动词：says；宾语从句：young children under the age of four and ____ less than 40 pounds must be in a child safety seat。宾语从句中的主干为：young children must be in a child safety seat。under the age of four and ____ less than 40 pounds用于修饰宾语从句主语children。动词weigh与名词children是主动关系，所以选择weighing。句意：交通法则规定四岁以下并且体重不超过四十磅的婴儿必须坐在婴儿安全座上。