听力短文

The virus causing AIDS enters the blood and quickly penetrates（渗透）

certain white cells in the body. / At first there is often little or no trace（痕迹）

of the virus at all. / This situation usually lasts for six to twelve weeks. / During this time the person is free of symptoms（征兆）/ and antibody（抗体）tests are negative. / The first thing that happens after infection / is that many people develop a flue-like illness. / This may be severe enough to look like glandular（有腺的）fever / with swollen glands in the neck and armpits腋窝/ tiredness, fever and night sweats. / Some of those white cells are dying, / virus is being released, / and for the first time the body is working hard to make correct antibodies. / At this stage the blood test will usually become positive. / Most people do not realize what is happening, / although when they later develop AIDS they look back and remember it clearly. / Most people have produce antibodies in about twelve weeks.

The Library of Congress is the national library of the United States. / It was founded in 1800 to serve the needs of the congressmen. / Today, it contains books, articles and documents on every subject imaginable. / Besides senators, congressmen and other government officials, / it serves libraries, researchers, artists and scientists throughout the country and the world. /The Library is one of the largest libraries in the world. / It has a collection of 74 million items which are housed in three buildings. / The bookshelves stretch for 350 miles. / Of the 18 million books, more than half are in languages other than English. / The main reading room is a great hall of marble pillars. / It is the center of activity in the library. / There is a computer catalog center with six terminals for quick access to information. / For greater speed and efficiency, / the library has installed an electric book – carrying system / that carries books from one building to another in only a few seconds.

Weak eyesight is a term that is generally used to refer to nearsighted eyes. / People who are nearsighted can see well at a short range, / but anything very far away is likely to be unclear. / The term "weak eyesight" is misleading, / for in nearsighted eyes the lens of the eye is actually too strong. / The nearsighted lens is so powerful that it focuses the light coming onto the eye so quickly. / Nearsightedness is common, and its growth may be graded; / often the unclearness of distant object is so slight at first / that a person may not recognize the condition. / Nearsightedness is frequently discovered first at school. / It is here that a student first realizes the difficulty of seeing words on the blackboard, / whereas others in the class have no trouble reading the blackboard at all. / After discovery, nearsightedness can easily be corrected. / You just needs a pair of glasses / which can decrease the power of the lens of the eye. / (161 words) Rice is very much under appreciated in the United States. / With the exception of Asian cooking, / rice is usually a side dish or combined with other ingredients. / Rice is very nutritious, low cost and easy to prepare food. / There are different types of rice available and the cooking time varies by type of rice. / Follow the package instructions for the amount of liquid necessary and the cooking times. / Both vary for each type of rice. / Regular white rice has been milled / to remove the hull comes in long, medium and short grains. / Long grained rice is the best for all-purpose use. / Brown rice has a pleasant nutty flavor and a firmer texture. / While white rice is cooked in about 15 minutes, / brown rice takes 45 to 50 minutes to cook. / When cooking rice do not be concerned if you have cooked rice left over. / There are some excellent recipes, which use cooked rice.

The relationship between a teacher and astudent can be either good or bad, helpful or harmful. / Either way, there lationship can affect the student for the rest of his life. / A good teacher-student