eplied. I was a little worried."可知，作者担忧是因为她无法叫醒儿子。故选B项。

　　3．What problem did the author and her son face?

　　A．They couldn't get out of the house.

　　B．They couldn't stop things from falling.

　　C．They couldn't find anything to hide under.

　　D．They couldn't remember what to do in an earthquake.

　　答案与解析：C　细节理解题。根据第三段的"Unfortunately, none of our furniture was designed for hiding under."可知，她们家里没有任何可躲避的地方。故选C项。

　　4．The author and her son most probably realized they should ________.

　　A．replace their furniture

　　B．build a stronger house

　　C．receive earthquake drills

　　D．watch the weather report often

　　答案与解析：A　推理判断题。根据全文内容以及最后一段的"But both my son and I knew what we should do, because we knew if there had been a really big earthquake this morning, we couldn't have escaped from it."可推断，作者和她儿子在这次地震中意识到应该未雨绸缪，为地震做好准备，故很有可能换家具。故选A项。

　　B

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