注意：

1）词数100个左右(开头和结尾已给出, 不计入总词数);

2）可以适当增加细节, 以使行文连贯。

Dear Tom,

Yours,

Li Hua

    Scientists in Argentina have created the world's first cow with two human genes that will enable it to produce human-like milk.

    Genetic engineering was used to introduce the "mothers' milk" genes into the animal before birth, according to the National Institute of Agribusiness Technology in Buenos Aires.

    As an adult, the cloned cow "will produce milk that is similar to that of humans", which will prove "a development of great importance for the nutrition of infants(婴儿)", said the institute. "The cloned cow, named Rosita ISA, is the first in the world with two human genes that contain the proteins present in human milk," said the statement.

    In April, scientists in China published details of research showing that they had created dairy cows which produced milk containing proteins found in human breast milk. But the Argentine team said the Chinese only introduced one human gene, while their research involved two, meaning the milk will more closely resemble that of humans.

    "Our goal was to raise the nutrition value of cows' milk by adding two human genes, which do good to the immune system of infants," said Adrian Mutto, from the National University of General San Martín which worked with the institute.

    Cristina Kirchner, President of Argentina, said that the scientific institute made all Argentines proud. She also said that she had refused the "honour" of having the cow named after her. "They came to tell me that the name is Cristina, but what woman would like to have a cow named after her? It appeared to me to be more proper to call it Rosita."

    If someone asked you to quantify (衡量) the time you spend online, how would you answer? If you're like one-fifth of Americans, you'd likely say "almost constantly." New research shows that 21 percent of Americans report that they're online more or less constantly.

    Andrew Perrin, a research assistant at Pew, did a survey about Internet use. During the survey, adults were asked how much they go online. 13 percent said they don't go online and 13 percent said they go online several times a week or less. Only 10 percent said they go online once a day and much larger quantities said they go online several times a day (42 percent) or "almost constantly" (21 percent).

    Interestingly, there wasn't a gender split (性别分化) when it came to near constant Internet use. Age seems to be the great divider: Only six percent of people over 65 said they were online that much. Those who reported that they were online all the time included 12 percent of 50- to 64-year-olds, 28 percent of 30- to 49-year-olds and 36 percent of 18- to 29-year-olds.

    Don't suppose that teenagers are online more than adults, however. In another survey, Pew found that while they did have a slight edge on adults in general when it came to "almost constant" Internet use, 24 percent said they were online pretty much all the time. They still fell greatly behind the 36 percent of adults between 18 and 29 years of age who were always online.

    Given that the United Nations considers unrestricted (无限制的) Internet access (接入) to be a human right, the number of Americans who report being online "almost constantly" could rise along with availability and affordability. But it remains to be seen whether being online all the time is actually something to long for, or how constant connectivity will affect American culture in the long term.

Book and bookmaking

    A book is a printed work that is meant to communicate. It's made up of pages that are usually enclosed in a protective cover. {#blank#}1{#/blank#}Among the countless types of books are novels, picture books, cookbooks, how-to books, poetry books, and textbooks.

    The first step in creating a book is for an author to write a manuscript (手稿). Then the author finds a publisher, or a company that makes and sells books. {#blank#}2{#/blank#}They make sure that the ideas are complete, that the writing is clear, and that there are no mistakes.

    Then the manuscript goes to a designer. This person arranges the text and pictures on the pages so that the book looks nice and is easy to read. {#blank#}3{#/blank#}

    Editors and designers continue working on the pages until they are perfect. The designed book is stored in computer files (文件).

    Next, the computer files are used to create printing plates, which are pieces of metal or plastic that have the book's text and pictures on them. Printing plates are put on printing presses and used to print the book.

    Early books were difficult to produce. The text was written by hand. As a result, books were expensive and hard for most people to get. {#blank#}4{#/blank#}

    The invention of printing changed that. In about 1450, a special type of printing press was invented in Germany. It could print many books quickly.

    Today books are published in every language. Personal computers have allowed people to publish their own books. Many books can be read or downloaded from the Internet.{#blank#}5{#/blank#}

A. A designer also creates the cover.

B. Books can have either a hard cover or a soft cover.

C. This has made books easier to get than ever before.

D. People have written books about all kinds of subjects.

E. Only wealthy and powerful people read these early books.

F. Books became available to ordinary people for the first time.

G. Editors at the publishing company help the author improve the manuscript.