问a .her younger brother is writer and her elder sister is a doctorher younger brother is writer and her elder sister is a doctor问a 为什么writer前面没有a ,doctor前面有a
问题描述：
问a .her younger brother is writer and her elder sister is a doctor
her younger brother is writer and her elder sister is a doctor
问a
为什么writer前面没有a ,doctor前面有a
答
a writer