Some people believe the Nazca Indians were 29 able to fly, perhaps in balloons.
答案：(B) somehow
somehow 意為「以某種（不明的）方式」：有人相信納斯卡人不知用什麼方法能夠飛行，或許是搭熱氣球；someday（將來某天）、sometime（某個時候）、somewhere（某處）都與句意不合。
答對率 34%。
四個 some- 開頭的字長得極像，你大概靠語感挑一個。它們的差別其實很整齊：somehow ＝ 以某種方式（不知道怎麼做到的）；someday ＝ 將來某一天；sometime ＝ 某個時候；somewhere ＝ 某個地方。「看空格前後缺的是「方式」「時間」還是「地點」。」
the Nazca Indians were ___ able to fly（納斯卡人…能夠飛行）——句子後面接 perhaps in balloons（或許是搭熱氣球），這個 perhaps 正好呼應 somehow 的不確定的語氣：怎麼飛的沒人知道。
More mysterious is the fact that they can be viewed only from the air.（更神祕的是這些圖案只能從空中看見）——正因為只能從空中看，才有人猜他們會飛。
somehow（不知怎麼地、以某種方式）、someday（將來某一天）、sometime（某個時候）、somewhere（某個地方）、somewhat（有點）。
In the desert of southwest Peru, enormous shapes, complex patterns, and thousands of perfectly straight lines are cut into the desert's surface. They are known as the Nazca lines and they 26 500 square kilometers. There are about fifty animal figures 27 275 meters long, including a monkey, a spider, and an "owl man." The last of these lines were drawn about 1,000 years ago.
More 28 is the fact that they can be viewed only from the air. Some people believe the Nazca Indians were 29 able to fly, perhaps in balloons. Others say the lines were landing areas for alien spaceships.
Maybe the lines were to carry water for farming, or were used as a calendar. The only thing certain is that the Nazca lines remain one of the world's most fascinating 30 mysteries.