问题补充：
It is amazing that the little boy can swim the river 100 meters wide.
A. across; measuring
B. over; measured
C. across; measure
D. through; measuring
答案：
(答案→)A. across; measuring
B. over; measured
C. across; measure
D. through; measuring
解析：考查介词和非谓语动词。across是个介词，swim across the river“游过那条河流”；2）meaure 100 meters wide在此处做后置定语，修饰the river.而measure作为“量起来为……。长度/宽度为...”时是不及物动词，表明the river和measure之间是主动关系，所以只能使用其现在分词measuring.
