1.theflu (大疫) 2.togetaflue (疫苗) 3.good (良好卫生习惯) 4.the (持续的时间)ofthe commoncold 5.littleproofofits (效力) 6. (维生素C的) acid7. at the (细胞的)level 8. (相橘类的)fruits9. In (补充)form 10. therecommendeddaily (定量) 11. stones(肾结石)12. vitamin D (缺乏症)13. (认知的)impairment14.to grow in (流行)amongconsumers 15.The （attack）ofavirus16. clinical (临床试验) 17.totakea (安慰剂)18.toleaveyou (易患)viral 19.tocausemore （danger）thangood20.toget (接种)