If there are （） in the repair work, please come to our duty engineer at once.

A . close the vent B . pump out the tank C . activate the fixed CO system D . cut off the heating coil

A . wharf B . wharves C . wharve D . wharf

A . Yes, they do. B . Yes, they are. C . No, there aren‘t. D . No, they don‘t.

A . savings banks B . saving bank C . saving banks D . savings bank

A . tie themselves to the unit so they won't drift with the current B . form a small circular group to create a warmer pocket of water in the center of the circle C . send the strongest swimmer to shore for assistance D . form a raft by lashing their life preservers together

A . Five. B . Six. C . Three. D . Four.

A . communications in the whole system will stop B . the global system will be damaged C . the back-up one will take its place D . the whole system will not work

A . zero B . at least one C . at least two D . at least four E . at least three

If there are abnormal files in ZXCTN device, they will be stored in directory()with name of().

A．A.swimming pools B．B.classes C．C.trainers

A、three radios/ two pianoes B、hundreds of photos/ thousands of tomatos C、two radios/ many photos D、two photos/ three radioes

Researchers at the Biorobotics (生物机械技术)Laboratory of McGill University in Montreal are building a robot , known as Micro Surgery robot-1(MSR- I for short), that will perform. delicate operations under the control of a human surgeon. The robot is specifically designed for performing eye surgery but could have other applications, such as the removal of brain tumors. The system could also be used to allow surgeons and their students to practise simulated surgery that feel like the real thing- without the real consequences for the patients. During the operations, the surgeon manipulates a set of control known as the master. These are connected through a high- performance computer to the robot. Both the master and the robot have two limbs, When the surgeon moves the masters' limbs, the robots limbs move in exactly the same way, except that the movements can be scaled down as much as a thousand times. This will eliminate hand tremor and poor accuracy and thus reduce the damage to the eye that can occur with present microsurgery techniques. Each of the robots limbs has a minimum movement of one micrometer---more than one hundred times the precision of the human hand. The computer also creates a three - dimensional robot' s eye view of the inside of the eye that the surgeon can see by wearing a virtual reality helmet (虚拟现实头盔) that has a small lens in front of each eye. To provide the surgeon with such a realistic experience, MSR-I must be able to move rapidly, but this requires extremely fast computing. To handle the computational demands of instant interaction, the McGill team is constructing its own parallel-processing computer., It is al so studying areas such as muscle mechanism, artificial intelligence and optics, and has a already built another micro robot MR- I, capable of manipulating a single living cell. Although commercial applications of the new system are not expected for several years, its basic mechanical components will be ready for testing in a few months, "The day when micro robots will be able to perform. surgery without human intervention is many years away," says Hunter, "in the meantime , a system such as MRS-I is a necessary precursor." The so-called "virtual reality "mentioned in this passage is actually. A．a surgical tool used for operations B．a computer system used to produce life- like illusions C．a new kind of applications in a visual technology. D a way to carry out operations in a visual sense

Fortunately, there is something definite which you can do. Protect Alarms can help to protect your house with a burglar alarm system which is effective, simple to operate and easily affordable. You must re-member that possessing a burglar alarm is no indication that your house is packed with valuable possessions. It quite simply indicates to unwelcome visitors that yours is one house they will not break into easily, so they carry on to an unprotected house where their hob is made a lot easier. Send now for our free leaflet telling you how we can protect your house quickly, easily and cheaply. Complete and tear off the slip below and post it to us. Postage is free. Alternatively, televice. It costs nothing to find out about Protect Alarms. Anyone who takes an interest in the crime rate will, according to the text, be aware that ______ . A．more burglars are being caught that ever before B．people have more possessions to worry about nowadays C．burglars are more at risk that they used to be D．homes are more likely to be broken into nowadays

【C5】______ of the world' s population is concentrated on only a small 【C6】______ of the earth' s land surface, in the rich valleys and 【C7】______ plains, because people up to the present time have 【C8】______ to congregate in place where the climate and soil make it easy to grow food and obtain shelter. A 【C9】______ world population and the discoveries of science 【C10】______ this pattern of distribution in the future. As men slowly learn to master diseases, control floods, prevent famines, and stop wars, fewer people die every year; and in 【C11】______ the population of the world is steadily 【C12】______ . When numbers 【C13】______ , the extra mouths must be fed. New lands must be brought 【C14】______ cultivation, or land already 【C15】______ , made to yield larger crops. In some areas the accessible land is largely so intensively cultivated 【C16】______ it will be difficult to make it 【C17】______ more food. in some areas the population is so dense that the land is divided into. units 【C18】______ tiny to allow for much improvement in farming methods. 【C19】______ a large part of this farming population drawn 【C20】______ into industrial occupations, the land might be farmed much more productively by modern methods. 【C1】______ A．scattered B．restrained C．separated D．resembled

A．0．66 B．0．75 C．1．0 D．1．4 E．2．0

A．toofewhogswillberaiseD B．thepricewillbelessthanthemarginalsocialcost． C．thepricewillbelessthanthemarginalsocialbenefit． D．thepricewillbelessthanthemarginalcosttohogfarmers．