What is the main purpose of this letter？

A . To act as ballast for light vessels B . To provide ventilation and drainage for cargo C . To secure the tarpaulins in place D . To support weakened bulkhead

A . seal the space between the piston and the liner B . reduce the amount of lube oil burned in the combustion chamber C . transmit heat from the piston to the cylinder liner D . damp out fluctuations of the piston side thrust

A . It is used to restart the router. B . It is used to bypass the configuration in NVRAM. C . It is used to enter ROM Monitor mode. D . It is used to view the lost password. E . It is used to save the changes to the configuration.

A . control fuel injection time more precisely B . control fuel injection rate more precisely C . meet the environmental requirements D . meet high engine speed requirement

A .  To enhance Spanning Tree troubleshooting on multilayer switches B .  To reduce the total number of spanning tree instances necessary for a particular topology  C .  To provide faster convergence when topology changes occur in a switched network D .  To provide protection for STP when a link is unidirectional and BPDUs are being sent but not  received E .  None of the other alternatives apply

A . to inspect if the cylinder has the water leakage B . to expel out the residual water/gas/oil from the cylinder C . to check if fuel supply is normal D . A and B

A．To welcome health care professionals B．To promote certain health services C．To discuss health workforce shortages D．To promote careers in health care

A．To attempt to sell a second-hand vehicle B．To place an order for a vehicle part C．To describe the kind of car she is looking for D．To request a mechanical service

A．To inform. people the severity of the millennium bug. B．To accuse some comes for being inactive. C．To advise people to abandon the computers. D．To tell the readers the way to solve the millennium bug problem.

A. to describe how American children spend their summer. B. to explain the needs of the modern working families. C. to discuss the problems of the current school calendar. D. to persuade parents to stay at home to look after their kids.

A．To compare guided tours B．To discover new places of interest C．To introduce a book series D．To show ways of writing for children

A．explain why couples grow alike B．tell how couples like each other C．discuss the function of marriage D．describe the life of happily-married couples

A．To point out similarities in Emerson"s essays and poems B．To prepare the students to read an essay by Emerson C．To compare Emerson"s concept of universal truth to that of other authors D．To show the influence of early United States society on Emerson"s writing 此题为多项选择题。

A．To invite people to take a breath in the Bay of Naples. B．To advise people to telephone Newmarket Air Holidays Ltd. C．To persuade people to tour in the area of the Mediterranean Sea. D．To attract people to go to Sant' Agata or Sorrento for sightseeing.

A．Reminding the company employees of how to send and receive mails B．Criticizing the company employees for some bad habits C．Informing the company employees of an important announcement from the post office D．Giving thanks to all the company employees

A．To advise America to learn from its mistakes. B．To tell the readers how to look at WikiLeaks. C．To discuss how to deal with WikiLeaks. D．To show readers how to stick to their rules.

A．To make a customer service complaint B．To congratulate on winning an award C．To request a special service D．To express gratitude to a company

A．To publicize a community event B．To solicit donations for a special cause C．To ask for public feedback on a proposal D．To announce a program change

A．To outline contrasting types of economic system. B．To explain the science of economic systems. C．To argue for the superiority of one economic system. D．To compare barter and money-exchange markets.

A．To advise that TV should be used for educational purpose B．To describe the harmful effects of TV on children C．To explain traditional views of influences that TV has had on children D．To suggest that television cannot be blamed for problems it doesn't cause