Indefinite Article ( A, An)

"A" is used for nouns that begin with a consonant sound.    e.g.  a pen;   a dog;    a bus;    a man;    a lion                          "An" is used for nouns that begin with a vowel sound /a/, /e/, /i/, /o/,/u/.                                                                                                  e.g.   an apple;   an orange;   an umbrella                                N.B. We also use 'an' before words that begin with a silent h.                 e.g. an hour;    an honest man "A", "An" are used : To describe a singular noun          e.g. I have a pencil and a rubber in my school bag. To talk about a person or thing for the first time          e.g. An elephant and a mouse are friends.                Would you like a hamburger? To talk about jobs         e.g. I'm a teacher. Before hundred, thousand, million        e.g. a hundred people              a million dollars    N.B. We don't use 'a' or 'an' before a plural noun or an uncountable noun.         e.g. We like dogs.                I drink water.