【Noairmeansdeath．Althoughwecannotseeitthereisairaroundus．Soairiseverythinganditgiveslifetoeverylivingthing．Badairmakespeopleill．Wemusthavefreshairtokeepushealthy．Inthecitythereareagreat】

　　Noairmeansdeath．Althoughwecannotseeitthereisairaroundus．Soairiseverythinganditgiveslifetoeverylivingthing．Badairmakespeopleill．Wemusthavefreshairtokeepushealthy．

　　Inthecitythereareagreatmanypeopleandtherearetoomanycarsrunningontheroads．Thegaswhichthecarsspread(扩散)outisfullofpoison(毒物)．Everydaywebreatheitinagainandagain．Thismakesusfeelsick．Besidessomanycarstherearemanyfactoriestoo．Fromthechimneysofthesefactorieswegetthesmokeusuallyinblackandgreycolor．Thiskindofthesmokewhenitmixestheairisdangeroustoourhealthitisbecausesmokecontains(包含)manypoisonoussolidandgases．Soinordertokeepushealthywehavetogoouttothecountrysidetobreathemorefreshair．Orwecangouphillstogetmorefreshair．

　　1．Whichofthefollowingbestexplainsthatnoairmeansdeath?

　　A．Badairmakespeoplesick． B．Aircan'tbeseenanywherearoundus．

　　C．Airgiveslifetoeverylivingthing． D．Freshairkeepspeoplehealthy．

　　2．Wheredopeopleusuallybreathefreshair?

　　A．Inbigcities． B．Ontheroads．

　　C．Inthecountryside． D．Aroundfactories．

　　3．Smokefromthechimneysisdangeroustoourhealth

　　A．whenitmakesairdirty B．ifitcontainspoisonoussolidsandgases

　　C．nomatterhowitspreadsout D．becauseitisinblackandgreycolor

　　4．Accordingtothepassageweknowthat ．

　　A．weshouldn'tgooutofdoorsasmuchaspossible

　　B．smokefromchimneysismoreseriousthangasfromthecars

　　C．agreatmanypeoplehavetobreatheairinagainandagain

　　D．goinguphillsisoneofthebestwaystokeephealthy

　　5．Thebesttitleforthepassageis ．

　　A．TheUseofAir B．BreathingAir C．FreshAir D．BadAir