uncle和aunt前面都是用an，u和a都是元音字母。a和an都是不定冠词，用来表示泛指，后接可数名词单数。a/an加单数名词可以泛指某一类事物中任何一个具有代表性的成员。例句：A puma is a wild animal that is a member of the cat family.Pumas have brownish-grey fur and live in mountain regions of North and South America.美洲虎是猫科家族的一员野外动物。它们有棕黑色的皮毛并生存于北美和南美的山区。

Aunt Mary volunteered to clean up the kitchen

玛丽阿姨主动要求清扫厨房。

'Dropping the charges has given racists a licence to kill,'said Jim's aunt.

“撤销指控等于是放纵种族主义者去杀人，”吉姆的阿姨说。

The foreign minister has become everybody's favourite Aunt Sally.

外交部长已成为众矢之的。

She kept her promise to visit her aunt regularly.

她信守诺言，定期去看望姑妈。

His natural mother was unable to care for him so he was raised by an aunt.

他的生母不能照顾他，所以他是姑姑抚养大的。

It turns out that her aunt and my cousin are one and the same.

原来她姑妈就是我表姐。

This is my aunt who's over from Canada.

这是我姑姑，她是从加拿大过来的。

My aunt lives in Canada.

我的姑母住在加拿大。

After her mother's death,Sara clung to her aunt more than ever.

萨拉在母亲去世后比以往任何时候都更依附于她的姨妈。

I was struck by her resemblance to my aunt.

我猛然发现她长得跟我姑姑很像。

He lives with an aunt who keeps house for him.

他和一位帮他料理家务的姑妈住在一起。

Her aunt was small,with a rather fussy manner.

她的姨妈个子矮小，为人相当挑剔。

There's been no trace of my aunt and uncle

没有我姑姑、姑夫的踪迹。

She wrote to her aunt in America

她给远在美国的姨妈写了封信。

It was a present from Aunt Vera.

这是薇拉姑妈送的礼物。

The studio is midway between his aunt's old home and his cottage.

工作室就在从他姑姑的老宅到他的小屋的中途。

Abby had been so deep in thought that she had walked past her aunt's car without even seeing it

阿比沉浸在自己的思绪中，以至于从她姨妈的车边经过时都没有注意到。

My grandmother and aunt will be there in my parents'stead.

我的祖母和姑妈将代替我的父母出席。

Aunt Mary wore shapeless black dresses.

玛丽姨妈总是穿一些没款没形的黑色裙子。

Her Aunt Sallie gave her an uncharacteristically extravagant gift

萨莉姨妈送给她一件贵得离谱的礼物。

He was an orphan and lived with his uncle.

他是个孤儿，和他叔叔一起生活。

Uncle Harry is terminally ill with cancer.

哈里叔叔癌症已到了晚期。

I don't have much contact with my uncle.

我和叔父甚少联系。

I'm going to visit my uncle.

我要去看我舅舅。

My uncle's branch of the family emigrated to Canada.

我们家族中我叔父的这一支移居到了加拿大。

He owed$20 000 in tax to Uncle Sam.

他欠美国政府2万元税款。

My uncle taught me to juggle.

我叔叔教我玩杂耍。

My uncle was a Falstaffian figure.

我的叔叔是个福斯塔夫式的人物。

He began to talk about the Ukraine of his uncle's day

他开始讲述他叔叔那个时代的乌克兰。

For years we were taught that Uncle Sam and foreign investment were the problem.

多年以来我们都被教导美国和外资乃是问题所在。

We have had problems in our family that I didn't dare tell Uncle.

我们家里有一些问题我以前不敢告诉叔叔。

Uncle Paul and I hardly know each other.

我和保罗叔叔几乎互不相识。

His uncle is dead,but his auntie still lives here.

他伯父已经过世，可他伯母还在这儿生活。

Uncle Herbert never argued,never spoke up for himself

赫伯特叔叔从不与人争吵，也从不为自己辩护。

Uncle,pa wants to see you.

舅舅，我爸爸想见你。

He vacated the flat and went to stay with an uncle

他搬出了公寓，住到了他的一个叔叔那里。

My Uncle Jim had a high fever

我叔叔吉姆发了高烧。

I knew how unbalanced Paula had been since my uncle Peter died

我知道葆拉自从我叔叔彼得去世后情绪一直很不稳定。

There's been no trace of my aunt and uncle

没有我姑姑、姑夫的踪迹。

Don't worry,Uncle Tim,your future is safe in our hands.

别担心，蒂姆大叔，你将来由我们照顾。

1、表示一类人或事物的名词（无论复数还是单数）前，如：

I like reading books.

我喜欢看书。

2、某些专用名词前，如：

I like China.

我爱中国。

3、不可数名词前，如：

Would you like a cup of water?

你要来杯水吗？

4、节日、季节、日期、月份、年份（年代前要加the，in the 1990's）前，如：

Today is Teachers’Day.（节日）

今天是教师节。

He was born in May in 1987.（月份、年份）

他出生于1987年5月。

5、称呼语前，如：

Good morning，sir？

早上好，先生。

6、代词后，如：

This pen is mine.

这支钢笔是我的。

7、科目名词前，如：

We will learn Chinese and history.

我们将学习中文和历史。

8、三餐前，如：

She goes to school after breakfast.

她吃完早饭后去上学。

9、球类运动前，如football：

We often play football.

我们经常踢足球。