The boy is to go to school..A. enough oldB. young enoughC. old enoughD. enough young

问题补充：

The boy is to go to school..

A. enough old

B. young enough

C. old enough

D. enough young

答案：

A. enough old

B. young enough

(答案→)C. old enough

D. enough young

解析： enough adj.足够的,修饰可数名词或不可数名词,可以放在名词前面,也可以放在名词后面;adv.足够地,修饰形容词、副词、动词,并放在其后。根据题意这个男孩要去上学应该是足够大,所以选C.