[填空题]Since its (invent) _______, the telephone has become one of the most important telecommunication instruments in the world.

[填空题]Since its (invent) ______, the telephone has become one of the most important telecommunication instruments in the world.

[填空题]How much has China reduced its population since 1970
China has already cut its rate of population growth by ______.

[单项选择]Since a circle has no beginning or end, the wedding ring is accepted as a symbol of ______ love.
A. successive
B. consecutive
C. eternal
D. insistent

[单项选择]Since 1975 there has been in the United States a dramatic decline in the incidence of traditional childhood diseases such as measles. This decline has been accompanied by an increased incidence of Peterson’s disease, a hitherto rare viral infection, among children. Few adults, however, have been affected by the disease.
Which of the following, if true, would best help to explain the increased incidence of Peterson’s disease among children ？（）
A. Hereditary factors determine in part the degree to which a person is susceptible to the virus that causes Peterson’s disease.
B. The decrease in traditional childhood diseases and the accompanying increase in Peterson’s disease have not been found in any other country.
C. Children who contract measles develop an immunity to the virus that causes Peterson’s disease.
D. Persons who did not contract measles in childhood might contract measles in adulthood, in which case the consequences of the disease would generally be more severe.
E. Those who have contracted Peterson’s disease are at increased risk of contracting chicken pox.

[单项选择]

A characteristic of American culture that has become almost a tradition is to respect the self-made man—the man who has risen to the top through his own efforts, usually beginning by working with his hands. While the leader in business or industry or the college professor occupies a higher social position and commands greater respect in the community than the common laborer or even the skilled factory worker, he may take pains to point out that his father started life in America as a farmer or laborer of some sort. This attitude toward manual (体力的)labor is now still seen in many aspects of American life.
One is invited to dinner at a home that is not only comfortably but even luxuriousl(豪华地)furnished and in which there is every evidence of the fact that the family has been able to afford foreign travel, expensive hobbies, and college education for the children; yet the hostess probably will cook the dinner herself, will serve it herself and will wash dishes afterwar
A. people tend to have a high opinion of the self-made man
B. people can always rise to the top through their own efforts
C. college professors win great respect from common workers
D. people feel painful to mention their fathers as labors