Deep inside a mountain near Sweetwater in East. Tennessee is a body of water known as the Lost Sea. It is listed by the Guinness Book of Would Records as the world’s largest underground lake. The Lost Sea is part of an extensive and historic cave system called Craighead Caverns.

　　The caverns have been known and used since the days of the Cherokee Indian nation. The cave expands into a series of huge rooms from a small opening on the side of the mountain. Approximately one mile from the entrance, in a room called “The Council Room,” many Indian artisfacts have been found. Some of the items discovered include pottery, arrowheads, weapons, and jewelry.

　　For many years there were persistent rumors of a large underground lake somewhere in a cave, but it was not discovered until 1905. In that year, a thirteen-year-old boy named Ben Sands crawled through a small opening three hundred feet underground. He found himself in a large cave half filled with water.

　　Today tourists visit the Lost Sea and ride far out onto it in glass-bottomed boats powered by electric motors. More than thirteen acres of water have been mapped out so far and still no end to the lake has been found. Even though teams of divers have tried to explore the Lost Sea, the full extent of it is still unknown.

　　66. The Lost Sea is unique because it is ________.

　　part of a historical cave system

　　the biggest underground lake in the world

　　listed in the Guinness Book of World Records

　　the largest body of water in Tennessee

　　67. The Craighead Caverns have been known ________.

　　A. through history B. since the time of the Indian nations

　　C. since 1905 D. since divers explored them

　　68. Who located the Lost Sea in recent times?

　　A. The Cherokee Indians. B. Tourists.

　　C. Ben Sands. D. Scientists.

　　69. What was found in “The Council Room”?

　　A. A small natural opening. B. A large cave.

　　C. Another series of rooms. D. Many old Indian objects.

　　70. It can be inferred from the passage that the Craighead Caverns presently serve as ____.

　　A. an underground testing site B. an Indian meeting ground

　　C. a tourist attraction D. a motor boat race course

　　Passage Three

　　Generations of Americans have been brought up to believe that a good breakfast is one life’s essentials. Eating breakfast at the start of the day, we have all been told, and told again, is as necessary as putting gasoline in the family car before starting a trip.

　　But for many people the thought of food first thing in the morning is by no means a pleasure. So despite all the efforts, they still take no breakfast. Between 1977 and 1983, the latest year for which figures are available, the number of people who didn’t have breakfast, increased by 33 percent.

　　For those who feel pain of guilt about not eating breakfast, however, there is some good news. Several studies in the last few years indicate that, for adults especially, there may be nothing wrong with omitting breakfast. “Going without breakfast does not affect performance,” said Arrold E. Bender, former professor of the nutrition at Queen Elizabeth College in London, “nor does giving people breakfast improve performance.”

　　Scientific evidence linking breakfast to better health or better performance is surprisingly inadequate, and most of the recent work involves children, not adults, “The literature”, says one researcher, Dr. Erresto at the University of Texas, “is poor”.

　　71. The latest year for which figures could be obtained is _______.

　　A. the year the author wrote the article B. 1977

　　C. any year between 1997 and 1983 D. 1983

　　72. For those who do not take breakfast, the good news is that _______.

　　several studies have been done in the past few years

　　the omission of breakfast does no harm to one’s health

　　adults have especially made studies in this field

　　eating little in the morning is good for health

　　73. “…nor does giving people breakfast improve performance” means ______.

　　anyone without breakfast does improve his performance

　　not giving people breakfast improve performance

　　having breakfast does not improve performance, either

　　people having breakfast do improve their performance

　　74. The word “literature” in the last sentence refers to _______.

　　A. stories, poems, plays, etc. B. written works on a particular subject

　　C. any printed material D. the modern literature of America

　　75. What is implied but NOT stated by the author is that _______.