题目内容：

The Myth of crop circles

Have you ever heard of the crop circles? It’s a magic event: crops in the field get curved（弯曲的）over one night and show different patterns（图案）. Most times, they show simple circles or circles with rings. So they are named “crop circles”.

It’s not a m_______ event. But in ancient times, people couldn’t see these patterns, because you need to see them from some h_______ places and there were no tall buildings in the fields. With the invention of planes, a lot of aerial（航空的）p_______ let people see the crop circles with their own eyes.

Some people say they are the work of tornado（龙卷风）; and some believe supernatural（超自然的）power c_______ them. But most people think it’s just a trick played by artists. According to some research, 80 percent of the crop circles may be man-made. But some facts are undeniable. At Stonehenge（英国巨石阵）in 1996, a pilot r_______ seeing nothing while flying above the place. Fifteen minutes later, a huge 900-foot pattern of 149 circles a_______. This took eleven scientists more than five hours to survey. How could human beings finish it in just 15 minutes? No one has a certain answer.

1.m________

2.h________

3.p________

4.c________

5.r________

6.a________