朝鲜语专业四级专业八级证书有没有含金量？

WAST stands for ______.

A．Western Australia Supply and Transport

B．Webster Aptitude Standard Test

C．Welsh Association of Sail Training

D．White Anglo-Saxon Protestants

Telecommunications stand for devices and systems that transmit electronic or optical signals across long distances. Telecommunications enables people around the world to contact one another, to access information instantly, and to communicate from remote areas. Telecommunications usually involves a sender of information and one or more recipients linked by a technology, such as a telephone system, that transmits information from one place to another. Telecommunications enables people to sand and receive personal messages across town, between countries, and to and from outer space. It also provides the key medium for delivering news, data, information, and entertainment.

Telecommunications devices convert different types of information, such as sound and video, into electronic or optical signals. Electronic signals typically travel along a medium such as copper wire or are carried over the air as radio waves. Optical signals typically travel along a medium such as strands of glass fibers. When a signal reaches its destination, the device on the receiving end converts the signal back into an understandable message, such as sound over a telephone, moving images on a television, or words and pictures on a computer screen.

Telecommunications messages can be sent in a variety of ways and by a wide range of devices. The messages can be seat from one sender to a single receiver (point-to-point) or from one sender to many receivers (point-to-multipoint). Personal communications, such as a telephone conversation between two people or a facsimile (fax) message (see Facsimile Transmission), usually involve point-to-point transmission. Point-to-multipoint telecommunications, often called broadcasts, provide the basis for commercial radio and television programming.

Telecommunications begin with messages that are converted into electronic or optical signals. Some signals, such as those that carry voice or music, are created in an analog or wave format, but may be converted into a digital or mathematical format for faster and more efficient transmission. The signals are then sent over a medium to a receiver, where they are decoded back into a form. that the person receiving the message can understand. There are a variety of ways to create and decode signals, and many different ways to transmit signals.

Individual people, businesses, and governments use many different types of telecommunications systems. Some systems, such as the telephone system, use a network of cables, wires, and switching stations for point-to-point communication. Other systems, such as radio and television, broadcast radio signals over the air that can be received by anyone who has a device to receive them. Some systems make use of several types of media to complete a transmission. For example, a telephone call may travel by means of copper wire, fiber-optic cable, and radio waves as the call is sent from sender to receiver. All telecommunications systems are constantly evolving as telecommunications technology improves. Many recent improvements, for example, offer high-speed broadband connections that are needed to send multimedia information over the Internet.

Personal computers have pushed the limits of the telephone system as more and more complex computer messages are being sent over telephone lines, and at rapidly increasing speeds. This need for speed has encouraged the development of digital transmission technology. The growing use of personal computers for telecommunications has increased the need for innovations in fiber-optic technology.

Telecommunications and information technologies are merging and converging. This means that many of the devices now associated with only one function may evolve into more versatile equipment. This convergence is already happening in various fields. Some telephones and pagers are able to store not only phone numbers but also names and personal information abo

A．Current development.

B．Transmission of message.

C．Computer networking.

D．Government regulation.

【M4】

During the traditional wedding ceremony, the

CD＃6bridal couple promises each other lifelong 【M1】______

devotion. Yet, about one out of four American

marriages ends in divorce. Since 1940, the

divorce rate has more than doubled, and

experts predict that, of all marriages that

occured in the 1970s, about【M10】% will end in 【M2】______

divorce. The USA is one of the highest divorce 【M3】______

rates in the world, perhaps even the highest.

What goes wrong? That fact that divorce is so

common in the United States does not mean that

Americans consider marriage a casual, unimportant

relationship. Just opposite is true. Americans 【M4】______

expect a great deal from marriage. They seek physical

, emotional, and intellectual compatibility.

They want to be loved deep and understood. It 【M5】______

is because Americans expect so much from

marriage that so many get divorce. They prefer 【M6】______

no marriage at all to a marriage without love

and understanding. Which typical American

optimist, they end one marriage in the 【M7】______

hope of that the next will be happier. With 【M8】______

no fault divorce laws in many states, it is

easier than never to get a divorce. Some American 【M9】______

women stay in unhappy marriages because they

do not have the education or job experience

to support themselves and their children.

But most American women believe that, ff necessary,

they can make it lonely without a 【M10】______

husband. All things considered, Americans

have little reason to continue an unhappy

marriage.

【M1】