Since 1965, when is equipment became operational, a devicecalled Eros has been helped to make sky traffic__1__ safe. Erosis short for Eliminate Range Zero Systemrange zero meaningcollision. Basically Eros is a computer system measures, withgreat speed and precision, closing__2__ speed ( the speed atwhich two objects are approaching each other ) and range ( thedistance apart of the objects ).Eros can warn aircraftsapproachable each other at jet__3__ speeds and can provide protection for as many as athousand aircraft in wide area. The pilot of an Eros−equipped aircraft heading for a collision hear awarning noise in his ear−phones__4_when his airborne computer calculates that he is within thirtyseconds or half a mile ( whichever occurs first ) of other aircraft.__5__ At the same time, a flashingred arrow on the device's indicator panel instructs him to climb. Simultaneously, in the otheraircraft, __6__ the signal is automatically reversed: the flashing arrow tells the pilot to climb. Thenewer Eros II system can accommodate a total of two thousands aircraft at one time within a140−mile radius__7__ Every three seconds, each Eros−equipped plane automatically reports toground stations and to similarly equipped aircraft their precise range, altitude and approach rate.The producers__8__ of Eros, the McDonnell Dougals Corporation in the U.S., are now studyingthe fitting of Eros and will do more to make__9__ the sky safer: they shall also lighten the work ofair−traffic__10__ controllers and increase the efficiency of airports.
參考答案及解析:
1. helped—helping.現(xiàn)在完成進行時
2. measures前加that/which.that/which引導定語從句，修飾先行詞a computer system
3. approachable—approaching.approaching為現(xiàn)在分詞，修飾aircraft，相當于that/which are approaching each other
4.hear—hears.其主語是the polit
5. other—another.相對于上提到的an Eros−equipped aircraft， 此處為另一架飛機
6. climb—descend.根據(jù)上下文的意義，一架飛機下降，另一架飛機上升，以免相撞
7.thousands—thousand.根據(jù)語法規(guī)則，數(shù)詞hundred 、thousand 、million等詞一般為單數(shù)形式
8. their—its.指上文中的主語each equipped plane
9.沒錯。10. shall—will.表示一般將來，shall常用于第一人稱，will則常用于第二和第三人稱