分类：教育/科学-学习帮助
问题：英语选择题，呼救！Didyouleavethedoorsandw 
Did you leave the doors and  firmly _________?You kown there are many burglars these days.A、To fasten B、To be fastened C、fastened答案是C，为什么不是B？
回答：选C.呵呵!
变成陈述句 :leave the doors and windows firmly fastened.....
为leave+宾语+宾补 的结构,the doors and windows是宾语,fastened 是宾补,说明宾语的状态,与宾补是被动的关系,所以要用过去分词:)
希望对你有帮助!