Use a (pronounced “uh”) with singular countable nouns starting with a consonant sound: a boy, a horse, a union. Use an with singular countable nouns that start with a vowel sound: an egg, an hour, an umbrella.

We use a or an to refer to any member of a group of singular countable nouns. A or an is used to introduce a noun for the first time. The is used afterward. For plurals, omit the article or use some if only certain ones are meant. Use the _____s afterward. Remember, a means “one.” Don’t use it with plurals (e.g. a Cheerios ).

When we generalize, we use the singular or the plural. It is important not to alternate. Remember to use the Simple Present for generalizations.

A manager makes $50,000 a year or Managers make $50,000 a year.

A vegetarian doesn’t eat meat or Vegetarians don’t eat meat.

When you define a word, don't say “...is when...” Use a noun to define a noun, a verb to describe a verb, and so on.

Define these countable nouns:

E.g. "A taxi driver is someone who drives clients to their destinations."

"An iPod is a gadget which plays compressed music files."

Notice that who refers to people whereas which is used for animals and things.