单选题Plastic sheeting should be wrapped around the tree in winner to ______ it from the wind and the frost.

单选题We decided to ______ roses in the front garden.

单选题Speaker A: Can you tell me something about your company?Speaker B:________. Our company was established in 1953. We produce a wide variety of electronic equipment,

单选题Cleaning woman in big cities usually get ______ by the hour.A. payB. payingC. paidD. to pay

单选题I took ______ tea than you. A. less B. few C. fewer D. little

单选题To save class time, our teacher has ______ students do half of the exercise in class and complete the other half for homework. A) us B) we C) our D) ours

单选题To maintain public______is not only the policemen's duty but also every citizen's responsibility. A. custom B. confidence C. security D. simplicity

单选题—Can I pay the bill by check? —Sorry, sir. But it is our rule that payment ______ be made in cash. A. can B. need C. shall D. will

单选题{{B}}Questions 11-15 are based on the following passage:{{/B}} Venus (金星) is known as the earth's "twin" because the two planets are so like each other in size. The diameter of Venus is about 7, 520 miles (12,100 km. ), smaller than that of the earth. No other planet comes closer to the earth than Venus. At its nearest approach it is about 25,000,000 miles (40,2000,000 km. ) away. As seen from the earth, Venus is the first planet or star that can be seen in the western sky in the evening. At other times, it is the last planet or star that can be seen in the eastern sky in the morning. When Venus is near its brightest point, it can be seen in daylight. Early astronomers called the object that appeared in the evening Hesperus, and Phosphorus in the morning. Later, they realized these two objects were the same planet. They named it Venus in honor of the Roman goddess of love and beauty.

单选题He is the only person who can ______ in this case because the other witnesses were killed mysteriously. [A] testify [B] charge [C] accuse [D] rectify

单选题There are two spare rooms in the building, (neither) of (them) (has) been provided (with) modern facilities.

单选题Baroque has been the term used by art historians for almost a century to ______ the dominant style of the period 1600--1750. A. determine B. designate C. devise D. depict

单选题"A roiling stone gathers no moss (苔藓)," but there is one living animal that does gather moss, the three-toed sloth (树懒) of South America. This slowest-moving member of the animal kingdom is so inactive that moss actually gathers on its body and turns it green—strange as it seems! Most of the sloth"s life is spent motionless, hanging upside down from a limb. And that is the way its hair grows. Long and coarse, the strands (串) from receptacles (花托) for the damp jungle algae (水藻) that turn the brown fur a mossy green. Actually this moss helps the animal survive because it serves as a perfect camouflage against the leaf trees and hides the sloth from the jungle"s swift-moving hunters. The sloth would have little chance of survival on the ground. With long, curved claws hooked over the limb of a leafy tree, it spends the long hot hours during the day drowsing and eating. Inch by inch, it strips the leafy limbs bare and crawls slowly down the trunk to find a new dining spot, but only at night. In addition to looking rather like a vegetable, the sloth is a strict vegetarian. Running out of its favorite leaf is about the only thing that will make a sloth move. Then its appetite may even force the animal into swimming a stream to reach a juicy succulent (多汁的植物). It will also force it into fighting to keep the tree all to itself. The sloth is lazy and prefers to be alone, but it will tolerate its own relatives!

单选题 (21) summary of the physical and chemical (22) of life must begin, not on the Earth, but (23) the Sun; in fact, (24) the Sun's very center. (25) is here that is to be found the (26) of the energy that the Sun constantly (27) space (28) light and heat. This energy is liberated at the center of the Sun as billions upon billions of nuclei hydrogen atoms (29) each other and (30) to form nuclei of helium, and, (31) doing so, (32) some of the energy that is stored in the nuclei of atoms. The output of light and heat of the Sun (33) that some 600 million tons of hydrogen (34) helium in the Sun every second. This the Sun (35) for several thousands of millions of years.

单选题The destruction of our natural resources and contamination of our food supply continue to occur, largely because of the extreme difficulty in affixing (把……固定) legal responsibility on those who continue to treat our environment with reckless abandon (放任). Attempts to prevent pollution by legislation, economic incentives and friendly persuasion have been met by lawsuits, personal and industrial denial and long delays—not only in accepting responsibility, but more importantly, in doing something about it. It seems that only when government decides it can afford tax incentives or production sacrifices is there any initiative for change. Where is industry's and our recognition that protecting mankind's great treasure is the single most important responsibility? If ever there will be time for environmental health professionals to come to the frontlines and provide leadership to solve environmental problems, that time is now. We are being asked, and, in fact, the public is demanding that we take positive action. It is our responsibility as professionals in environmental health to make the difference. Yes, the ecologists, the environmental activists and the conservationists serve to communicate, stimulate thinking and promote behavioral change. However, it is those of us who are paid to make the decisions to develop, improve and enforce environmental standards, I submit, who must lead the charge. We must recognize that environmental health issues do not stop at city limits, county lines, state or even federal boundaries. We can no longer afford to be tunnel-visioned in our approach. We must visualize issues from every perspective to make the objective decisions. We must express our views clearly to prevent media distortion and public confusion. I believe we have a three-part mission for the present. First, we must continue to press for improvements in the quality of life that people can make for themselves. Second, we must investigate and understand the link between environment and health. Third, we must be able to communicate technical information in a form that citizens can understand. If we can accomplish these three goals in this decade, maybe we can finally stop environmental degradation, and not merely hold it back. We will then be able to spend pollution dollars truly on prevention rather than on bandages.

单选题His constructive proposal for improving the program is ______of our attention.

单选题Children who are described as mildly mentally mentally handicapped are often upset to hear themselves described as such, and such terms as "children with learning difficulties" are now ______.

单选题For the first time, we found______ that allow us to connect the first phase of human evolution and the second phase. A. theories B. morasses C. frescos D. fossils