a, an用法区别
a用在以辅音音素开头的单词前，an用在以元音音素开头的单词前，判断一个单词是元音开头还是辅音开头，要根据其读音，而不是根据首字母。

如：an hour, an honest boy，a useful book
There is an “f” in the word “five”.
(在“five”中有字母“f”。

)
我们可以这样来记忆：不见元音不加an，不看字母看发音。

(1)在26个字母中，前面用an的字母有：a，e，f，h，i，l，m，n，o，r，s，x，其他用a。

(u不是)
(2)以u开头的单词，要注意区别。

如：
an umbrella，an unusual story，an unhappy boy，a university，a useful book, a unit (3)以e开头的单词，要注意区别。

如：
an egg, a European boy
(4)以h开头的单词，要注意区别。

如：
an hour, an honest boy
(5)注意这几个数字（1,11，与8相关的数字）
a one-year-old boy
an eveven-year-old boy
an eighty-year-old man
_____1-year-old girl
_____ 11-year-old boy,
____ 18-year-old girl
1.There is ____“u” in the word “use”.
2.There is ____ “h” in the word “there”.
3.There isn't ____ university in our town.
4.Tony is ____ honest boy.
5. London is ____ European city.
6. _____ 8-year-old boy is playing games.
7.There are 60 minutes in ___ hour.
8. Liu Xiang is ___ unusual player.
总结：需注意
1)在26个字母中，前面用an的字母有12个。

(2)以字母u开头的单词。

(3)以字母e开头的单词。

(4)以字母h开头的单词。

(5)注意的数字。

习题：
选择a或an或者不填(用/来表示)
pen bag
apple big apple
banana orange
oranges orange pen
hour house
umbrella university
用a/an填空：
①Is it Chinese book or English book?
②This is ring, and it is orange ring.
③Mary is English teacher. Tom is Chinese teacher.
④This is bike. It’s old bike.
⑤This is telephone number.
⑥That is ID card.
⑦I lost my keys. It’s set of keys.
⑧It’s apple, not pear.
⑨This is peach. That’s orange.
⑩You have banana, but I have egg.
①Is there umbrella on the desk?
②There is island in the sea.
③There is picture on the card.
④I have old book.
⑤apple is a kind of fruit.
⑥There is armchair in the living room.
⑦I’d like egg.
⑧Look, there is bird in the tree.
⑨Is there map on the wall?
⑩There is bench in the park.。