He has flu.和He has a toothache.这两句话一个他得了流感,一个是他牙痛.为什么flu不要用a《an》

he has flu说成he has a flu行吗? He has a flu .哪里错了? He has a stomach ache 和 He has flu 为什么一个有A一个没有A He has flu.和He has a toothache.这两句话一个他得了流感,一个是他牙痛.为什么flu不要用a《an》 改疑问和否定!绝对有分!1、I often watch TVin the evening.2、He has a flu. he has a one 和 he has one 那个对 dave has a flu .so he must stay in bed .改错 he has a dream He has a temperature he has become a He has a cat mr.wang has stay in_bed because he has _ flu.the He not has a sister.和He only has a sister.哪个对? he has a headache =he has a( ) ( )his head He has a picture____( darw) He already has a lover Has he got a computer? he has a round face