Usage- "A" versus "An"

In grammar, the terms "a" and "an" are referred to as indefinite articles. They're used before singular nouns. But what's the difference and how do you know which one to use? In most instances, the article "a" can be used. The exception, however, comes when the noun that follows starts with a vowel (the letters 'a,' 'e,' 'i,' 'o,' and 'u').

Let's look at some examples!

1.) I borrowed a book from the library.
2.) A thunderstorm is predicted for tomorrow.
3.) Did you see a movie this weekend?

4.) An elephant was part of the circus.
5.) My sister packed an umbrella in her car.
6.) Did you taken an English class this year?

How good do you think you are at using "a" and "an" correctly?

Test your skills by playing the "Rags to Riches" game found here: http://www.quia.com/rr/53245.html. Then, come back & report how you did. Don't forget to include your thoughts on the activity. Was it fun? Did you challenge yourself? Would you recommend this activity to others who'd like to practice their "a" versus "an" skills?