不少考生開始備考2017年職稱英語考試，為了幫助大家更好地備考職稱英語考試，yjbys網小編為大家提供了相應的練習題，以下是職稱英語考試理工類A模擬題：概括大意，希望對大家的備考有所幫助。
第3部分：概括大意與完成句子(第23"--'30題，每題l分，共8分)下面的短文後有兩項測試任務：(1)第23——26題要求從所給的6個選項中為第2——5段的每段選擇1個最佳標題;(2)第27——30題要求從所給的6個選項中為每個句子確定1個最佳選項。
Maglev Trains
(1) A few countries are using powerful electromagnets to develop high-speed trains, called maglev trains. Maglev is short for magnetic levitation, which means that these trains float over a guide way using the basic principles of magnets to replace the old steel wheel and track trains.
(2) If you've ever played with magnets, you know that opposite poles attract and like poles repel each other. This is the basic principle behind electromagnetic propulsion. Electromagnets are similar to other magnets in that they attract metal objects, but the magnetic pull is temporary. You can easily create a small electromagnet yourself by connecting the ends of a copper wire to the positive and negative ends of an AA-cell battery. This creates a small magnetic field. If you disconnect either end of the wire from the battery, the magnetic field is taken away.
(3) The magnetic field created in this wire-and-battery experiment is the simple idea behind a maglev train rail system. There are three components to this system: A large electrical power source, metal coils lining a guide way or track, and large guidance magnets attached to the underside of the train.
(4) The big difference between a maglev train and a conventional train is that maglev trains do not have an engine- at least not the kind of engine used to pull typical train cars along steel tracks4. The engine for maglev trains is rather unnoticeable. Instead of using fossil fuels, the magnetic field created by the electrified coils in the guideway walls and the track combines to propel the trains.
(5) The magnetized coil running along the track, called a guideway, repels the large magnets on the train's undercarriage, allowing the train to levitate between 1 to 10 cm above the guideway.
Once the train is levitated, power is supplied to the coils within the guideway walls to create a unique system of magnetic fields that pull and push the train along the guideway. The electric current supplied to the coils in the guideway walls is constantly alternating to change the polarity of the magnetized coils. This change in polarity causes the magnetic field in front of the train to pull the vehicle forward, while the magnetic field behind the train adds more forward thrust.
(6) Maglev trains float on a cushion of air, eliminating friction. This lack of friction allows these trains to reach unprecedented ground transportation speeds of more than 500 kph, or twice as fast as the fastest conventional train. At 500 kph, you could travel from Paris to Rome in just over two hour
23. Paragraph 3 __________
24. Paragraph 4 __________
25. Paragraph 5 __________
26. Paragraph 6 __________
A. The main components of the maglev train system
B. High-speed maglev due to zero friction
C. The working principle of the maglev train
D. Differences between polarity and magnetic field
E. Comparison of maglev trains with traditional ones
F. Maglev with a powerful motor
27. Several countries in the world are using strong electromagnets __________
28. You can connect a wire to the positive and negative ends of a battery __________
29. A unique system of magnetic fields is created by the coils __________
30. The frictionless maglev train enables you __________
A. to develop a maglev train rail system
B. to explain why maglev trains are faster
C. to pull and push the train forward
D. to create a magnetic field
E. to experiment with the maglev train
F. to travel from Paris to Rome in about two hours
答案與解析：
23.A。第三段列舉了磁浮列車的三個組成部分：動力源、金屬線圈和磁鐵。選項A概括了第三段的內容。
24.E。第四段就磁浮列車和傳統火車進行了比較：磁浮列車沒有發動機而傳統火車有發動機。選項E用comparison來概括是準確的。
25.C。第五段比較詳細地介紹了為什麼磁浮列車會向前運動，也就揭示了磁浮列車的工作原理。C項中說working principle是正確的。
26.B。在第五段解釋了磁浮列車浮起和向前運動的原理之後，作者在第六段中解釋了磁浮列車速度奇快的原因：去除了傳統火車的.車輪與鐵軌的摩擦。B選項說高速源於零摩擦，是正確的。
27.A。選A的依據是本文第一段第一句：A few countries using powerful electromagnets to develop high-speed trains，called maglev trains.
28.D。第二段說，把電線與乾電池相連線就能產生一個小磁場，而磁浮列車的運動原理與此相同。第二段第三句“You can easily create a small electromagnet yourselfby connecting the ends of a copper wire to the positive and negative ends of an AA-cell battery.”是選擇D的依據。
29.C。第五段的第二句，即“Once the train is levitated，power is supplied to the coils within the guideway walls to create a unique system of magnetic fields that pull and push the train along the guideway.”，是選擇C的依據。
30.F。本文最後一句提到時速500公里的磁浮列車從巴黎到羅馬只需約2小時這個例子來說明磁浮列車速度很快。
