问题描述：
Doyouknowthatitisyourimmunesystem(免疫系统)workingagainstthevirus……中的主旨句
Doyouknowthatitisyourimmunesystem(免疫系统)workingagainstthevirusthatmakesyouuncomfortablewhengettingacold,butnotthevirusitself?Sowhenyouhavegotastrongimmunesystem—andthevirusisstrongenoughtoo—youwillpossiblygetterriblecoldsymptoms(症状)suchashavingaheadache,havingahighfever,sneezingorcoughing,
VitaminCwon'tstopacold.ItissaidthatVitaminCworksbyincreasingwhitebloodcells.
However,manytestshaveshownthatitdoesnotpreventcolds.Atbest,itonlyreducesthetimeofsymptoms.
Stayingindoorswon'tprotectyou.Oneofthemostlikelysources(根源)ofcoldvirusesisyourcomputermouseordesk.Astudyofthecoldvirusinofficesfoundthat46percentofcomputermiceand45percentoftelephoneshadcoldvirusesonthem.
Wearingwarmclotheswon'tprotectyou.Coldsaremorecommoninautumnandwinter.That'sbecausethecool,wetandcoldweatherdrivespeopleindoors,wherevirusesmaymoreeasilyjumpfromonepersontothenext.Andthedistinctpeak(高峰期)incoldsisinSeptemberandFebruary,whichlikelybecauseofthereturnofstudentstoschoolsandcollegesafterthesummerandwinterholidays.
Oldwivesarerightaboutchickensoup.Grandmothers'chickensoupisanoldcureforcoldsforalong6me.Scientistssayitistrue.Chickensoupdoeshelpcureacold,somanywivesusuallycookchickensoupfortheirfamilymembersincoldwinters.
