今约6，700年前已开始食用玉米，比之前所认为的时间提前了约两千年。

　　1．What would be the best title for the passage?

　　A．Ancient popcorn was eaten about 2,000 years earlier than thought in Peru

　　B．A new discovery revealed the mystery about corn

　　C．How was corn cooked in ancient Peru and South America?

　　D．National Popcorn Day and the new－found corn remains in Peru

　　答案：A标题判断题。由文章主旨段第一段并纵观全文可知，文章讲的是新的研究发现，人类开始食用玉米的时间比我们认为的还要早大约2,000年，故选A。

　　2．From the passage we can learn that microfossils of corn ________ .

　　A．showed that people began cooking corn about 5,000 years ago

　　B．offered detailed information on the size of the ancient corncobs

　　C．showed the specific shape of the ancient corncobs

　　D．were analyzed by scientists via radiocarbon dating

　　答案：A　细节理解题。根据第三段第一句话中的"Previously, evidence of corn as a food about 5,000 years ago had mostly come from what are called microfossils"可知，玉米微化石显示人们在大约5,000年前已开始以玉米为食物。

　　3．What can we know about the newly found corn remains?

　　A．They revealed people in Paredones and Huaca Prieta never roasted a corncob directly over a flame.

B．They revealed people in Paredones and Huaca Prieta lived mainly