单选题The national debt is the sum total of financial obligations the national government A B incurs by borrow from governments, international institutions, or its C own population. D

单选题A supernova, the explosive death of a star, temporary attains a brightness of 100 million suns or more.

单选题According to the passage, scientists cannot explain which of the following aspects of squirrel behavior?

单选题New York City's (theatrical district) was (concentrated the) Bowery from 1860 to t875, and (around) 1900 the avenue (became) a center for the Yiddish theater.

单选题A moth possesses two pairs of wings _____ as single pair and are covered with dustlike scales.

单选题The word "link" in line 23 is closest in meaning to

单选题Drinking water----excessive amounts of fluorides causes the enamel of teeth to become brittle and to chip off, leaving a stained or mottled effect.

单选题The people native to the northwest coast of North American have long A be known for wood carvings of stunning beauty and extraordinary quality. B C D

单选题According to the passage, Krzysziof Pendereckj is known for which of the following practices?

单选题Probably not speech of so few words has ever been as celebrated as Lincoln’s Gettysburg Address.

单选题Adolescence is a transitional stage in human development from the beginning A B of puberty to the attainment of the emotion, social, and physical maturity of C adulthood. D

单选题Trip to Japan Student A: Hi, Susanne. I didn"t realize you ______. How was your trip? Student B: Oh, hi, Ron. The trip was great, but I must say, I am ______. The visit to Japan was ______ fifteen days of eating, drinking and long ______ traveling by train. Now that I"m back home, I can ______! Student A: Wow! Sounds fun, did you have good weather? Student B: Sure, if you like heat and humidity. I love heat so I ______. And, once Tokyo seemed unbearably hot, we ______, with lots of yummy sushi and cold beer and ______ to visit Kagoshima. It was a true adventure. Student A: So, what did you do in Kagoshima? Isn"t there a big volcano there? Student B: Yes, there is an active volcano that is ______. We took the boat ______ and stayed ______. It was pretty neat. I"ve never been ______ with a volcano, the thing could blow at any time! Student A: Sounds exciting and hot! You ______ of Tokyo only to be ______. Student B: Well, not exactly. It was still hot in the south, but we had the fresh ocean breezes to ______ so it was a most enjoyable time. I"ll go back for sure. Student A: Wasn"t it hard to communicate ______, though? I"ve heard lots of Japanese people study English but most are ______ actually using it. Student B: Actually, things did go very smoothly for us. One of my ______ had lived in Japan for a number of years right after college. He was really good at speaking Japanese when all else failed. More importantly, he knew how to Japanese people so they wouldn"t feel embarrassed about any English mistakes. Student A: Really? How did he do that? Student B: One method was to ______. When they responded he would repeat what they said ______. Eventually, they ______ what little English they knew to help us out. The Japanese are very polite. Student A: I think everyone knows that. Why didn"t your friend just speak to them in Japanese and then ______? It seems that would have been a better plan. Student B: Yeah, but it was fun to ______ a conversation. Once the Japanese person started speaking English, they would usually continue. We met some really interesting people that way and also got some really good ______. Student A: I never thought of that. Looks like I"ll have to ______ Spanish if I want to pretend I don"t really know how to speak it. Perhaps I can ______ some Latin hearts when I go to Colombia next year. Student B: You"d better start studying now. I"ve heard your Spanish and you"ve got a lot to learn before you can fake it. Student A: Thanks for ______. Your Spanish isn"t so hot either. Student B: True, but I do recall getting ______ in Spanish 101 than you did. Remember when you told the teacher you thought her beard was very sexy because you mixed up the pronunciation. Student A: How can I forget? I"m sure that was ______ I got a C instead of a B in that course.

单选题In western North America .......... form the Great Divide, which separates the areas from which waters flow either eastward to the Atlantic or westward to the Pacific.

单选题The attraction of opposite charges is one of the force that keep electrons in orbit around of nucleus of an atom.

单选题In the dark abyss of the deep sea __________ is produced by luminescent fish.

单选题A (variation) of collodion photography was the tintype, (which) captured images on a black (or) dark brown metal plate (instead. from on glass. A. variation B. which C. or D. instead

单选题Much of northern Canada lies within the Arctic Circle, and ______ ice or the sparse vegetation known as tundra.

单选题The spearmint plant, which grows to about three feet height, has stalk less leaves and la*, tapering spikes of flowers that are usually pink or lilac.

单选题Based on the information in the passage, it can be inferred that low-fire clays are MOST appropriate for making objects that