第30题: [单项选择]The police warned the residents in the area to keep their doors and windows ______ at night. A. closed B. closing C. to close D. to be closed 参考答案:A 答案解析:[解析] 本题考查过去分词的应用。本题句意为:警察告诫这一地区的居民晚上 关好门窗。
[知识点] keep sth.后可以接现在分词和过去分词,现在分词强调动作的持续性, 过去分词表强调事物的状态。