补全短文1 The function ofpower transmission/powernetworks/step-down substations and connected transmissionequipment/transmission at highvoltage/power network operation2 In ( ) such as U.S.Asome advanced countries/great advantages on economy and environmentalprotection/good homogenization of distribution/whole process management is strengthened3 Circuit breakers are automaticallyto control electrical power networks/to switch the current which can be from a few amperes/to perform any switching operation after long periods/of the highest importance for high reliability/of the circuit breaker4，Fuel cells are devices thatthere is no storage capacity in a fUelcell/further development is under way/as they are being developed there have been some applications/many cells are operated in series to obtain voltages/supply alternating current from fuel cells5 Many large cities are anythingthere is still something that can beuseful/there is no time to be lost/it can be put to use again/more and more machines are designed for this purpose/building beautifUl cities out of garbage is only a dream6,The weather in winterThey can sleep for a long time/We call this kind of sleep in wintertime“hibernation/Hibernating animals don’t need to eat much because they don’t move/So they don5t need to worry about bad weather and other dangerous animal/As it gets warmer and warmer in spring, the sleeping animals begin to wake up and lookaround for food7,The body that isIt circles the Earth and is therefore know as a satellite of the Earth/A satellite stays in orbit because the planet gravitational force keeps pulling it into a circle/The bigger and heavier a body is, the greater is its force of gravity/To get out into space we have to overcome the Earths gravitational pull/Artificial satellite can be used for various purpose8，The secondary equipmentsthe equipments that provide protecting, monitoring/the equipments that send the command signal/current values in secondary system/5 A rated current of the current transformer secondary winding/50V rated voltage of PT secondary side9,A sudden change in the configurationby the operation of a circuitbreaker/determine the insulation requirements of transmission line/the cost of transmission and line failure rat/at both opening and closing of circuit breakers/by means of circuit breaker dosing resistor in 500kV system10,The high voltage power transmitted from power planfs step-upsubstation to step-down substatio/the powerline that transmits the power from step-downsubstation/the overhead transmissionline/lightning frequently happening andheavy raining/large spanning line section11 ,The aim of introducing marketa wholesale market/a retail market/to agreeon the price and quantity to be traded/toregister as a market customer/to chooseelectricity suppliers12,Electric power is a mostthe lack of electricity (a blackout)/itsunavailability/social disorder, and evennational tragedy/its growth rate/high electricpower consumption per capita13,There are numerous examplesthe research and development/the fake andreal items/new chemicals/the intellectualproperty/physical property14, Electrical energy is the presencestatic electricity/electrical charge/electricalenergy/Alternating current/Electricalpotential15,Many people think ofSustainable/the best known is photovoltaiccells/inefficient/the collected energy is used toheat a fluid/efficient16,Electrical energy conservationreducing energy consumption can beundertaken at home/making use ofalternative clean energy sources/contributing to climate change/turning thethermostat up in the summer and down inthe winter/looking for other opportunities forelectrical energy conservation in the home17,Advanced Distribution AutomationThe electrical power grid/distributionsystems/at lower voltages/to control smallerentities/for a number of reasons18,Solar energy is laudedlike satellites in Earth orbit/buildings andfuturistic cars/such as a battery/to collect thesun's energy/United States19, The American idea offrom the very beginning/how much itemscost/have paid for/after the sale/Thecustomer service representative20,The necessity of reliabledeveloping countries/there are morepeople/renewable energy systems inparticula/highly reliable/For this reason21, “Look it up in the dictionaryBut it was not until 1604 that a book ofuncommon English words appeared/Eachtime, it has been updated/Dictionaries thatlist all kinds of words are known as generaldictionaries/General dictionaries are not theonly kind/Thus there are many kinds ofspecial dictionarie22,temperature,pressure,specificParameters of the medium/the rise intemperature/external forces/heattransfer/internal energy23,according to the mode of energyNuclear,wind,solar/supplies power tousers/supplies steam to the user/fuel supplyand ash disposal/newly scheduled power24,the most important pumpsIt must be located/motor frequency/threesets/two of them/it pressurizes and。