根据表格回答：
能发出超声波的有 ；
能听到超声波的有 ；
能听到次声波的有 ．
昆虫飞行时翅膀都要振动，蝴碟每秒振翅5﹣6次，蜜蜂每秒振翅300～400次，当它们都从你身后飞过时，凭你的听觉 [ ]
A．能感到蝴蝶从你身后飞过
B．能感到蜜蜂从你身后飞过
C．都能感到它们从你身后飞过
D．都不能感到它们从你身后飞过．
蝙蝠、海豚；狗、猫、蝙蝠、海豚；狗；B．
Is the world really going mad? 1._____day I was sittng in a restaurant 2._____ a quick drink and a talk with a few friends when it suddenly 3._____ me that almost everyone in the restaurant was smoking. It wasn’t long 4._____ the whole room was 5._____ with smoke. I asked with an apology for 6._____ to open a window to stop myself 7._____! Nowadays air pollution is something that hardly question any more. However, I still can’t walk down the street in any of the big cities without 8._____ that people are 9._____ the air pollution. It is time for the government departments of the world to introduce emission(废气排放) controls on all cars and 10._____ the public transport system(公共交通体系) to encourage people to 11._____ their cars at home. A friend of mine takes flying lesson each morning and it really makes him 12._____ when he climbs above the smog layer(烟雾) and looks down 13._____ it and thinks: “I’m breathing that!” This kind of 14._____ results from the bad management of resources. Waste things can 15._____ should, be treated properly. House building, road 16._____, and industrial development are all earthmoving(or earth-reducing) operations and can change the balances of 17._____ created over millions of years. I would like to 18._____serious studies done on all these main works before they are built. Also, there should be 19._____ national parks set up to keep the most beautiful parts of our countries in their natural 20._____. 小题1:.
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