题目内容
Radar is very important in aviation（the aircraft industry）today. It was first introduced in the Second World War. The British used it in the great air battles over England in 1940. The British fighter planes had to be in exactly the right place at exactly the right time to meet the enemy bomber（轰炸机）. In order to get there, the fighter stations had to be warned long before the bombers actually appeared. They also had to know the course the bombers were following. This would have been impossible without radar.The Germans also used radar later in the war when the great air raids（袭击）against their cities began. On both sides the system was almost the same in a number of ways. The heart of the radar warning system was the “operations centre”. This was a huge system of rooms, usually below the ground. Radar showed the position of the enemy bombers while the bombers were still far away. In the centre of the main operations room there was usually a huge map on a large table. The position of the bombers was also shown on this table. Anybody who looked at it could see immediately where the bombers were at that moment. The people in the radar centre also had to decide where the bombers were going, or what the likely targets（目标）were. When this had been calculated the people in those places were warned. As they hurried to air raid shelters below the ground, fighter planes were taking to the air. The fighters were never out of radio contact（联络）with the radar centre.
At night, radar was a pair of eyes that guided the fighters to the bombers that they could not see. A radar controller on the ground told the pilot exactly where to go. Usually the pilot himself did not see the bomber until he was a few seconds away from it. Then he would open fire. None of these things could have happened without radar.
1．Radar was used by the British in 1940 to ________.
A．guide bombers to their targets in the daylight
B．get fighters away from other British fighters they could not see
C．guide fighters to the right place in order to meet the German bombers
D．guide bombers to their targets at night
2．The Germans began to use radar ________.
A．earlier than the British
B．later than the British
C．after the Second World War
D．almost at the same time as the British
3．An air raid shelter is a place where people ________.
A．shoot at bombers
B．hide from bombers
C．keep bombs
D．keep radar
4．Radar helped night fighter pilots to ________.
A．see bombers long before they could to without it
B．get close to the bombers before they could see them
C．open fire on bombers that they could not even see
D．get back to the fighter station after the battle
解析：
| 1．C 参看：The British fighter planes had to
be in exactly the right place at exactly the right time to meet the enemy
bomber．
2．B 由“the Germans also used radar later in the way when the great air raids against their cities began”表明德国晚于英国。 3．B 由“this was a huge system of rooms，usually below the ground”可知，藏在地下的目的是远离敌机。 4．B 第三段表明应用这种设备在夜间所起到的巨大作用，第一句话就是答案。
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