The key the string was put into the door to stop the kite .
A. tie to;flying away
B. tying to;fly away
C. tied to;flying away
D. tied to;fly away
网友回答
A. tie to;flying away
B. tying to;fly away
(答案→)C. tied to;flying away
D. tied to;fly away
解析：考查非谓语动词和固定短语。The key和动词tie to之间是动宾关系，所以要用过去分词形式，排除A,B；stop the kite 用的是阻止某人做某事结构，stop…(from)doing…结构。所以选C。