单选题The main difference between a nurse-manager and a head nurse is that the former ______. A. is a member of the Medical Executive Committee of the hospital B. has to arrange the work shifts of the unit's nurses C. can make decisions concerning the medical treatment of a patient D. has full responsibility in the administration of the unit's nurses

单选题Scientists used to explore【31】the surface of the ocean. Now they【32】below the surface, too. They want to know about the ocean water and the【33】and animal life【34】in the ocean. In 1934 the scientist William Beebe dived 3 , 000 feet below the surface in a hollow steel ball. In 1935 Auguste Piccard dived 10, 330 feet. In 1960 his son Jean dived to a【35】of 35, 800 feet. All these early dives were deep. But the divers could not stay down for very long. They had to【36】the surface after a few seconds. Scientists needed to stay down longer to study life below the surface.【37】, they succeeded. Cousteau, a Frenchman, was able to【38】down to a depth of【36】feet for one month and to a depth of 90 feet for a week. Now scientists are developing even【39】equipment. With this new equipment, men can stay【40】the surface for days or【41】weeks. In 1962 Consteau【42】a research station 35 feet below the surface. Then in 1964 he set up another station on the ocean floor of the Red Sea. This was the first undersea station to operate【43】help from the surface. Many countries are now studying undersea【44】. The Soviet Union has an undersea laboratory in the Crimean Sea. The United States has a laboratory 50 feet【45】on the ocean floor【46】the Virgin Islands. In 1970 five men lived there for two weeks. Then a【47】of five women scientists stayed in the laboratory.【48】came other teams of men. All were there to explore the ocean depths and【49】plans for the use of its resources. Scientists hope to find enough【50】, vegetable, and animal wealth there to provide food for the whole world.

单选题This book will show the readers ______ can be used in other contexts. A. how that they have observed B. how what they have observed C. that how they have observed D. that they have observed

单选题______ it is to listen to music!

单选题Guthrie's contiguity principle offers practical suggestions for how to break habits. One application of the threshold method involves the time young children spend on academic activities. Young children have short attention spans, so the length of time they can sustain work on one activity is limited. Most activities are scheduled to last no longer than 30 to 40 minutes. However, at the start of the school year, attention spans quickly wane and behavior problems often result. To apply Guthrie's theory, a teacher might, at the start of the year, limit activities to 15 to 20 minutes. Over the next few weeks the teacher could gradually increase the time students spend working on a single activity. The threshold method also can be applied to teaching printing and handwriting. When children first learn to form letters, their movements are awkward and they lack fine motor coordination. The distances between lines on a page are purposely wide so children can fit the letters into the space. If paper with narrow lines is initially introduced, students' etters would spill over the borders and students might become frustrated. Once students can form letters within the larger borders, they can use paper with smaller borders to help them refine their skills. The fatigue method can be applied when disciplining disruptive students who build paper airplanes and sail them across the room. The teacher can remove the students from the classroom, give them a large stack of paper, and tell him to start making paper airplanes. After the students have made several airplanes, the activity should lose its attraction and paper will become a cue for not building airplanes. Some students continually race around the gym when they first enter their physical education class. To employ the fatigue method, the teacher might decide to have these students continue to run a few more laps after the class has begun. The incompatible response method can be used with students who talk and misbehave in the media center. Reading is incompatible with talking. The media center teacher might ask the students to find interesting books and read them while in the center. Assuming that the students find the books enjoyable, the media center will, over time, become a cue for selecting and reading books rather than for talking with other students. In a social studies class some students regularly fall asleep. The teacher realized that using the board and overhead projector while lecturing was very boring. Soon the teacher began to incorporate other elements into each lesson, such as experiments, and debates, in an attempt to involve students and raise their interest in the course.

单选题But the depth of a novel and the value of its artistic and ideological feature do not depend on the theme-either______or significant

单选题Participants in the Shanghai Co-operation Forum ______ regional teamwork to promote investment and economic development. A. cursed B. echoed C. bounced D. hailed

单选题______, the market will have to overcome some of the highest hurdles. It's seen in a long time.

单选题National poverty was ______ by rapid population growth.

单选题Many drama critics (considered) Richard Burton's interpretation of Hamlet superior (than) Sir Lawrence Olivier's version (produced) several years (earlier).

单选题The crotch rivet would not have been removed, ______.

单选题Artificial intelligence deals partly with the______between the computer and the human brain. A. profile B. mighty C. analogy D. leakage

单选题The human ear contains the organ for hearing and the organ for balance. Both organs involve fluid-filled channels containing hair cells that produce electrochemical impulses when the hairs are stimulated by moving fluid. The ear can be divided into three regions: outer, middle, and inner. The outer ear collects sound waves and directs them to the eardrum separating the outer ear from the middle ear. The middle ear conducts sound vibrations through three small bones to the inner ear. The inner ear is a network of channels containing fluid that moves in response to sound or movement. To perform the function of hearing, the ear converts the energy of pressure waves moving through the air into nerve impulses that me brain perceives as sound. Vibrating objects, such as the vocal cords of a speaking person, create waves in me surrounding air. These waves cause the eardrum to vibrate with the same frequency. The three bones of the middle ear amplify and transmit the vibrations to the oval window, a membrane on the surface of the cochlea, the organ of hearing. Vibrations of me oval window produce pressure waves in the fluid inside me cochlea. Hair cells in the cochlea convert the energy of the vibrating fluid into impulses that travel along the auditory nerve to the brain. The organ for balance is also located in the inner ear. Sensations related to body position are generated much like sensations of sound. Hair cells in the inner ear respond to changes in head position with respect to gravity and movement. Gravity is always pulling down on the hairs, sending a constant series of impulses to the brain. When the position of the head changes—as when the head bends forward—the force on the hair cells changes its output of nerve impulses. The brain then interprets these changes to determine the head's new position.

单选题During the period of economic recession, daily necessities were in short supply and had to be ______.

单选题if only the committee ______ the proposal and put them into effect as soon as possible. A) accept B) have accepted C) accepted D) should accepted

单选题There is no end to the magic within this circle of the world we live in. The greatest magicians today are 1 the physicists and chemists, the mathematicians and astronomers: the wise men seeking the answers 2 the riddles of earth and universe. But 3 of them can tell us how to walk 4 a floor, "by the law of gravitation" 5 the readiest answer 6 that. Gravitation is 7 the most familiar thing in all the world, and we were all brought 8 on the story of Newton and his apple and the law of gravitation. 9 physicists have begun to say that gravitation may be 10 an illusion. If it is an illusion, 11 it is pure magic that 12 our feet on the ground and our furniture 13 floating off into space. And who cares, 14 the magic works and the illusion is 15 ? It is all a matter of vocabulary 16 , for no two scholars have ever agreed 17 a definition of magic; but there is no denying 18 every time man has finally understood and explained a 19 he has ceased to call it magic and called it 20 instead.