Does he have a stomach ache 请问里面的这个a是起什么作用?怎么翻译?

does,have,headache,he,a,) Does he have a son. Does he have a _____(网球)?Yes,he does.xiexie Does he have a tennis racket? Does he have a ( ) brothers or sister Does he have a r___ face. Does he have a birthday card? Does he ______(have) a bike? does he have a book?对吗? Does he have a ____ (crime) record? does he have a bag的does是什么意思 Does he have a coccer.中的Does he 后为什么要跟have不跟has 为什么Does he have a tennis ball?这里用have? Does he have a beard?为什么have 不是has呢, What does he have? Does he have a apple or a pear?回答用什么Does he have a apple or a pear?回答用 Yes,he has.还是Yes,he does. Does Jim have a soccer ball?Yes ,he does 这个问答中为什么 答句中要 有does Does he have a temperature,doctor?为什么加a