1 . An international team of scientists has discovered a stellar black hole in Earth’s “cosmic backyard” containing the mass of 70 suns.
It’s a black hole that forms after stars die, collapse, and explode. Researchers had long believed that the size limit was only 20 times the mass of our sun because as these stars die, they lose most of their mass through explosions that force matter and gas swept away by stellar winds.
This theory has now been toppled by LB-1, the newly discovered black hole. Located about 15,000 light years away, it has a mass 70 times greater than our sun, according to a press release from the Chinese Academy of Sciences.
“Black holes of such mass should not even exist in our galaxy (星系), according to most of the present models of stellar evolution,” said Liu Jifeng, head of the team that made the discovery.
“LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation.”
Scientists are now scratching their heads at how LB-1 got so huge.
The team has proposed some theories. LB-1’s sheer size suggests that it “was not formed from the collapse of only one star,” the study said — instead, it could potentially be two smaller black holes orbiting each other.
Another possibility is that it formed from “fallback supernova (超行星).” This is when a supernova — the last stage of an exploding star — ejects (喷射) material during the explosion, which then falls back into the supernova, creating a black hole. This fallback formation is theoretically possible, but scientists have never been able to prove or observe it.
There are several types of black holes and stellar black holes like LB-1 are on the smaller side, according to NASA. Supermassive black holes are much bigger — they can be billions of times the mass of our sun.
Scientists believe supermassive black holes may have connection with the formation of galaxies, as they often exist at the center of the mass star stems but it is still not clear exactly how, or which form first.
1. According to scientists, what might account for the formation of LB-1?| A．The material ejected in the explosion of a supernova. |
| B．The smaller black holes moving around each other. |
| C．The evolution of the solar system. |
| D．The collapse of a certain star. |
| A．Confirmed | B．Strengthened. | C．Overturned. | D．Refused. |
| A．To inform readers of the basic knowledge about black holes. |
| B．To share the recent development of the black hole discovery. |
| C．To show the importance of discovering black holes for science. |
| D．To report achievements scientists have made in black hole theory. |
| A．The Latest Discovery of Galaxies |
| B．Proposed Theories of Black Holes |
| C．The Possible Formation of the Black Holes |
| D．Biggest Stellar-mass Black Hole Discovered |
2 . I am an active playgoer and play-reader, and perhaps my best reason for editing this book is a hope of sharing my enthusiasm for the theater with others. To do this I have searched through dozens of plays to find the ones that I think best show the power and purpose of the short play.
Each play has a theme or central idea which the playwright(剧作家) hopes to get across through dialogue and action. A few characters are used to create a single impression growing out of the theme. It is not my intention to point out the central theme of each of the plays in this collection, for that would, indeed, ruin the pleasure of reading, discussing, and thinking about the plays and the effectiveness of the playwright. However, a variety of types is represented here. These include comedy, satire, poignant drama, historical and regional drama. To show the versatility(多面性) of the short play, I have included a guidance play, a radio play and a television play.
Among the writers of the plays in this collection, Paul Green, Susan Glaspell, Maxwell Anderson, Thornton Wilder, William Saroyan, and Tennessee Williams have all received Pulitzer Prizes for their contributions to the theater. More information about the playwrights will be found at the end of this book.
To get the most out of reading these plays, try to picture the play on stage, with you, the reader, in the audience. The houselights dim(变暗). The curtains are about to open, and in a few minutes the action and dialogue will tell you the story.
1. What do we know about the author from the first paragraph?| A．He has written dozens of plays. | B．He has a deep love for the theater. |
| C．He is a professional stage actor. | D．He likes reading short plays to others. |
| A．Stating the plays’ central ideas. | B．Selecting works by famous playwrights. |
| C．Including various types of plays. | D．Offering information on the playwrights. |
| A．Control their feelings. | B．Apply their acting skills. |
| C．Use their imagination. | D．Keep their audience in mind. |
| A．A short story. | B．An introduction to a book. |
| C．A play review. | D．An advertisement for a theater. |
3 . I must have always known reading was very important because the first memories I have as a child deal with books. There was not one night that I don't remember mom reading me a storybook by my bedside. I was extremely inspired by the elegant way the words sounded.
I always wanted to know what my mom was reading. Hearing mom say, “I can’t believe what’s printed in the newspaper this morning,” made me want to grab it out of her hands and read it myself. I wanted to be like my mom and know all of the things she knew. So I carried around a book, and each night, just to be like her, I would pretend to be reading.
This is how everyone learned to read. We would start off with sentences, then paragraphs, and then stories. It seemed an unending journey, but even as a six-year-old girl I realized that knowing how to read could open many doors. When mom said, “The C-A-N-D-Y is hidden on the top shelf,” I knew where the candy was. My progress in reading raised my curiosity, and I wanted to know everything. I often found myself telling my mom to drive more slowly, so that I could read all of the road signs we passed.
Most of my reading through primary, middle and high school was factual reading. I read for knowledge, and to make A’s on my tests. Occasionally, I would read a novel that was assigned, but I didn’t enjoy this type of reading. I liked facts, things that are concrete. I thought anything abstract left too much room for argument.
Yet, now that I’m growing and the world I once knew as being so simple is becoming more complex, I find myself needing a way to escape. By opening a novel, I can leave behind my burdens and enter into a wonderful and mysterious world where I am now a new character. In these worlds I can become anyone. I don’t have to write down what happened or what technique the author was using when he or she wrote this. I just read to relax.
We’re taught to read because it’s necessary for much of human understanding. Reading is a vital part of my life. Reading satisfies my desire to keep learning. And I’ve found that the possibilities that lie within books are limitless.
1. Why did the author want to grab the newspaper out of mom’s hands？| A．She wanted mom to read the news to her. |
| B．She was anxious to know what had happened. |
| C．She couldn't wait to tear the newspaper apart. |
| D．She couldn't help but stop mom from reading. |
| A．her unique way to locate herself |
| B．her eagerness to develop her reading ability |
| C．her effort to remind mom to obey traffic rules |
| D．her growing desire to know the world around her. |
| A．It would help her update test-taking skills. |
| B．It would allow much room for free thinking. |
| C．It would provide true and objective information. |
| D．It would help shape a realistic and serious attitude to life. |
| A．explore a fantasy land |
| B．develop a passion for leaning |
| C．learn about the adult community |
| D．get away from a confusing world |
4 . First aid is emergency care for a victim of sudden illness or injury until more skillful medical treatment is available. First aid may save a life or improve certain vital signs including pulse, temperature, a clear airway, and breathing. In minor emergencies, first aid may prevent a victim’s condition from worsening and provide relief from pain. First aid must be given as quickly as possible. In the case of seriously injured, a few minutes can make the difference between complete recovery and loss of life.
First aid measures depend upon a victim’s needs and provider’s level of knowledge and skill. Knowing what not to do in an emergency is as important as knowing what to do. Improperly moving a person with a neck injury , for example, can lead to permanent spinal (脊柱的) injury and paralysis (瘫痪)。
Despite the variety of injuries possible, several basic rules of first aid apply to all emergencies. The first step is to call for professional medical help. The victim, if conscious (有意识的), should be reassured that medical aid has been requested, and ask for permission to provide any first aid. Next, assess the scene, asking other people or the injured person’s family or friends about details of the injury or illness, any care that may have already been given, and preexisting conditions such as diabetes (糖尿病) or heart trouble. The victim should be checked for the medical card that describes special medical conditions. Unless the accident scene becomes unsafe or the victim may suffer further injury, do not move the victim.
First aid requires rapid assessment of victims to determine whether life-threatening conditions exist. One method for assessing a victims condition is known by ABC, which stands for:
A — Airway: is it open and clear?
B — Breathing: is the person breathing? Look, listen, and feel for breathing.
C — Circulation: is there a pulse? Is the person bleeding extremely?
Check skin color and temperature for additional indications of circulation problems.
1. Before we give first aid to a victim, it is very important for us to ___________________.| A．make sure what to do and what not to do | B．refer to all kinds of handbooks on first aid |
| C．remove the ring or bracelet he/she may be wearing | D．take him/her to a hospital at once |
| A．professional doctors | B．the victim’s family members |
| C．the victim’s friends | D．those who are not necessarily professional doctors |
| A．Checking whether there is a pulse. | B．Looking, listening and feeling for breathing. |
| C．Replacing his/her medical card. | D．Examining whether the airway is open and clear. |
| A．the importance of protecting the accident scene. | B．some basic knowledge about first aid. |
| C．what professional medical help is. | D．who can give first aid. |
