enough足够的；充足的
①enough 用作形容词，意为"足够的；充足的"， 修饰名词时，常放在名词前。
time enough足够的时间
You'll have enough time/time enough to relax.
你将有足够的时间放松。
②enough 用作副词，意为"足够地；充分地"， 可修饰形容词或副词，要放在被修饰的形容词或副词之后。
It's warm enough in the room. 屋子里够暖和了。
He runs quickly enough. 他跑得足够快。
③enough还可用作代词，意为"足够，充分，充足"， 可做主语或宾语。
Did you have enough yesterday? 昨天你吃饱了吗？
④"。 . .enough(for+名词／代词＋）to do sth. "结构意为"（对于某人／某物而言）足够······做某事"， 可与 so. . .that. . . (如此······以至于······)进行同义句转换。
The box is light enough for the boy to carry.
＝The box is so light that the boy can carry it.
这个箱子足够轻，这个男孩能搬动。
eg：Cathy checked her paper______so that she could get good grades this time.
A.careful enough
B.enough careful
C.enough carefully
D.carefully enough
解析：我们可用"语法分析法"解答本题。
careful 为形容词，意为"认真的"；
carefully 为副词，意为"认真地"。
结合选项可知句意为"凯西足够认真地检查了她的试卷，以便这次地可以取得好成绩"。
此处应用副词修饰动词 checked, 排除A、B两项；enough意为"足够地"， 修饰形容词或副词时应位于其后，故选D.
