The boy was curious about how the waste paper was into a model kite.
A. improved
B. united
C. transformed
D. mixed
网友回答
A. improved
B. united
(答案→)C. transformed
D. mixed
解析：A提高B联合，团结，结合C改变，转变，变化D混合。句意;男孩很好奇废纸是怎样变成风筝模型的。故选C。Transform...into把。。。转变成。。。