不定冠词的基本用法
1.表示“一”的含义。
Give me a pen please.
We go shopping twice a week.
2.泛指某个人或东西。
Yesterday we visited an English secondary school.
She picked up a magazine and began to read.
3.表示一类人或东西。
He works as a language teacher in that university.
As a writer， he is successful.
Even a child can answer this question.
可数名词单数出现，泛指用不定冠词，特指用定冠词。一个可数名词的单数不能自己单独出现。
