单选题"Do you want to wait?""Three weeks______too long for me to wait."

单选题Natural flavorings and fragrances are often costly and limited in supply. For example, the vital ingredient in a rose fragrance is extracted from natural rose oil at a cost of thousands of dollars a pound; an identical synthetic substance can be made for 1% of this cost. Since the early twentieth century, success in reproducing these substances has created a new industry that today produces hundreds of artificial flavors and fragrances. Some natural fragrances are easily synthesized; these include vanillin, the aromatic ingredient in vanilla, and benzaldehyde, the aromatic ingredient in wild cherries. Other fragrances, however, have dozens, even hundreds of components. Only recently has it been possible to separate and identify these ingredients by the use of gas chromatography and spectroscopy. Once the chemical identity is known, it is often possible to synthesize them. Nevertheless, some complex substances, such as the aroma of fresh coffee, have still not been duplicated satisfactorily. Many of the chemical compounds making up these synthetics are identical to those found in nature, and are as harmless or harmful as the natural substances. New products must be tested for safety, and when used in food, must be approved by the U.S. Food and Drug Administration. The availability of synthetic flavors and fragrances has made possible a large variety of products, from inexpensive beverages to perfumed soap to used cars with applied "new car odor."

单选题High boots were the______for women last year.

单选题CEO stands______Chief Executive Officer. A．at B．to C．for D．on

单选题In every cultivated language there are two great classes of words which, taken together, comprise the whole vocabulary. First, there are those words 81 which we become acquainted in daily conversation, which we 82 , that is to say, from the 83 of our own family and from our familiar associates, and 84 we should know and use 85 we could not read or write. They 86 the common things of life, and are the stock in trade of all who 87 the language. Such words may be called "popular", since they belong to the people 88 and are not the exclusive 89 of a limited class. On the other hand, our language 90 a multitude of words which are comparatively 91 used in ordinary conversation. Their meanings are known to every educated person, but there is little 92 to use them at home or in the market-place. Our 93 acquaintance with them comes not from our mother"s 94 or from the talk of our school-mates, 95 from books that we read, lectures that we 96 , or the more 97 conversation of highly educated speakers who are discussing some particular 98 in a style appropriately elevated above the habitual 99 of everyday life. Such words are called "learned", and the 100 between them and the "popular" words is of great importance to a right understanding of linguistic process.

单选题Mr. Brown's condition looks very serious and it is doubtful if he will ______.

单选题In Hong Kong, doctors reported that, for unclear reasons, 12 recovered SARS patients had ______ weeks after they had been discharged -- spurring fears that people might be infectious even after they'd left isolation. A. recovered B. relapsed C. reexamined D. re-diagnosed

单选题Herman"s success is due to his hard work and his ability to formulate plans which will get work done efficiently.

单选题We don't plan to go to the concert, and so they don't.

单选题Through many years of evolution, your body has learned bow to respond to stress basing on its instinct for survival.

单选题A 50-ft wave travels at speeds ______ 20 m. p. h. , and anyone who's too slow at the approach risks being smashed.

单选题At the World Literacy Center, an organization that works to help people read, the helpers work hard, enabling them to successfully reach their goals.

单选题The well-known Garub Site, unearthed in 1997, shows that {{U}}man had made living{{/U}} there as early as 5,000 years ago.

单选题It was not until she arrived at the classroom she realized she had forgotten her coursebook.

单选题After the lecture the students shook hands with the visiting professor______turn.

单选题New York City surpassed the other Atlantic seaports in {{U}}partly{{/U}} because it developed the best transportation links with the interior of the country.

单选题The recent conference on the effective use of the seas and oceans was another attempt resolving major differences among countries with conflicting interests.

单选题If the jewelry is marked 14 parts of gold mixed with 10 parts of base metal, it will always bear ______ mark.

单选题The country will no longer be plagued by turmoil .

单选题Old Henry Ford won the hearts of the Americans with the wonderful Mode T, Uthe like of which/U was never seen before and has never been seen since.