题目

下列各组中的两种物质作用，反应条件（温度或者反应物用量）改变，不会引起产物种类改变的是( ) A . Na和O2 B . NaOH溶液和CO2 C . Na2O2和CO2 D . AlCl3溶液和NaOH溶液 答案：COne windy spring day, I observed young people having fun using the wind to fly their kites. Multicolored creations of varying shapes and sizes filled the skies like beautiful birds dashing and dancing in the exciting atmosphere above the earth. As the strong winds gusted against the kites, a string kept them in check.Instead of blowing away with the wind, they arose against it to achieve great heights. They shook and pulled, but the controlling string and the clumsy tail kept them in tow(牵引), facing upward and against the wind. As the kites struggled and trembled against the string, they seemed to say, “Let me go! Let me go! I want to be free!” They flew beautifully even as they fought the forced restriction of the string. Finally, one of the kites succeeded in breaking loose. “Free at last,” it seemed to say, “Free to fly with the wind.”Yet freedom from control simply put it at the mercy of an unsympathetic gentle wind. It flew ungracefully to the ground and landed in a twisted mass of weeds and string against a dead bush. “Free at last”. Free to lie powerless in the dirt, to be blown helplessly along the ground, and to settle down lifeless against the first roadblock.How much like kites we sometimes are. There always exist misfortunes and restrictions, rules to follow from which we can grow and gain strength. Prohibition is a necessary counterpart to the winds of opposition. Some of us pulled at the rules so hard that we never fly fast to reach the heights we might have obtained. If we keep all the commandment(戒律), we will never rise high enough to get our tails off the ground.Let us each rise to the great heights, recognizing that some of the prohibitions are actually the steady force that helps us climb and achieve.1.In the passage the writer watched _______.A. many young people flying multicolored kitesB. many birds dashing and dancing in the skyC. many young people enjoying the sunny dayD. the strong winds blowing against the sky2.What didn’t happen to the freed kite?A. It was blown helplessly around.B. It lay powerless in the dirt.C. It was trapped in a dead bush.D. It kept flying freely in the air.3.What is the purpose of the author in writing this passage?A. To give up tips on how to fly kites effectively.B. To warn us that freedom is actually powerless.C. To teach us a lesson that rules are important in life.D. To explain that restrictions are really unnecessary.4.Which of the following is the best title for the passage?A. Where to Fly B. Fly with RestrictionsC. Why to Fly Kites D. Fly to Freedom