Here are 20 simple rules and tips to help you avoid mistakes in English grammar. For more comprehensive rules please look under the appropriate topic (part of speech etc) on our grammar and other pages.

1. A sentence starts with a capital letter and ends with a period/full stop, a question mark or an exclamation mark.

  • The fat cat sat on the mat.
  • W here do you live?
  • M y dog is very clever!

2. The order of a basic positive sentence is Subject-Verb-Object. (Negative and question sentences may have a different order.)

  • John loves Mary.
  • They were driving their car¬†to Bangkok.

3. Every sentence must have a subject and a verb. An object is optional. Note that an imperative sentence may have a verb only, but the subject is understood.

  • John teaches.
  • John teaches¬†English.
  • Stop! (i.e.¬†You stop!)

4. The subject and verb must agree in number, that is a singular subject needs a singular verb and a plural subject needs a plural verb.

  • John¬† works ¬†in London.
  • That monk¬†eats ¬†once a day.
  • John and Mary¬†work ¬†in London.
  • Most people¬†eat ¬†three meals a day.

5. When two singular subjects are connected by or , use a singular verb. The same is true for either/or and neither/nor.

  • John or Mary¬†is ¬†coming tonight.
  • Either coffee or tea¬†is¬†fine.
  • Neither John nor Mary¬†was¬†late.

6. Adjectives usually come before a noun (except when a verb separates the adjective from the noun).

  • I have a¬†big¬†dog.
  • She married a¬†handsome Italian¬†man.
  • (Her husband is¬†rich.)

7. When using two or more adjectives together, the usual order is opinion-adjective + fact-adjective + noun. (There are some additional rules for the order of fact adjectives.)

  • I saw a¬†nice French¬†table.
  • That was an¬†interesting Shakespearian¬†play.

8. Treat collective nouns (e.g. committee, company, board of directors) as singular OR plural. In BrE a collective noun is usually treated as plural, needing a plural verb and pronoun. In AmE a collective noun is often treated as singular, needing a singular verb and pronoun.

  • The committee¬†are ¬†having sandwiches for lunch. Then¬†they ¬†will go to London. (typically BrE)
  • The BBC¬†have¬†changed¬† their ¬†logo. (typically BrE)
  • My family¬†likes ¬†going to the zoo. (typically AmE)
  • CNN¬† has¬†changed¬† its ¬†logo. (typically AmE)

9. The words its and it's  are two different words with different meanings.

  • The dog has hurt¬†its¬†leg.
  • He says¬†it's ¬†two o'clock.

10. The words your and you're  are two different words with different meanings.

  • Here is¬†your¬†coffee.
  • You're ¬†looking good.

11. The words there, their and they're  are three different words with different meanings.

  • There¬†was nobody at the party.
  • I saw¬†their ¬†new car.
  • Do you think¬†they're¬†happy?

12. The contraction he's  can mean he is OR  he has. Similarly, she's  can mean she is OR  she has, and it's  can mean it is OR  it has, and John's  can mean John is OR  John has.

  • He is¬†working
  • He has¬†finished.
  • She is¬†here.
  • She has¬†left.
  • John is¬†married.
  • John has¬†divorced his wife.

13. The contraction he'd  can mean he had OR  he would. Similarly, they'd  can mean they had OR  they would.

  • He had¬†eaten when I arrived.
  • He would¬†eat more if possible.
  • They had¬†already finished.
  • They would¬†come if they could.

14. Spell a proper noun with an initial capital letter. A proper noun is a "name" of something, for example Josef, Mary, Russia, China, British Broadcasting Corporation, English.

  • We have written to¬†Mary.
  • Is¬† China¬†in¬† Asia?
  • Do you speak¬†English?

15. Spell proper adjectives with an initial capital letter. Proper adjectives are made from proper nouns, for example Germany ‚Üí German, Orwell ‚Üí Orwellian, Machiavelli ‚Üí Machiavellian.

  • London is an¬†English¬†town.
  • Who is the¬†Canadian ¬†prime minister?
  • Which is your favourite¬†Shakespearian¬†play?

16. Use the indefinite article a/an  for countable nouns in general. Use the definite article the  for specific countable nouns and all uncountable nouns.

  • I saw¬†a bird¬†and¬† a balloon¬†in the sky.¬†The bird¬†was blue and¬†the balloon¬†was yellow.
  • He always saves some of¬†the money¬†that he earns.

17. Use the indefinite article a  with words beginning with a consonant sound. Use the indefinite article an with words beginning with a vowel sound. 

  • a cat,¬† a game of golf,¬†a human endeavour,¬†a Frenchman,¬† a university (you-ni-ver-si-ty)
  • an apple,¬† an easy job,¬†an interesting story,¬†an old man,¬†an umbrella,¬† an honorable man (on-o-ra-ble)

18. Use many or few  with countable nouns. Use much/a lot or little  for uncountable nouns. see Quantifiers

  • How many dollars¬†do you have?
  • How much money¬†do you have?
  • There are¬†a few cars¬†outside.
  • There is¬†little traffic¬†on the roads.

19. To show possession (who is the owner of something) use an apostrophe + s for singular owners, and s + apostrophe for plural owners.

  • The boy's¬†dog. ¬†(one boy)
  • The boys'¬†dog. ¬†(two or more boys)

20. In general, use the active voice (Cats eat fish) in preference to the passive voice (Fish are eaten by cats).

  • We¬† use¬†active in preference to passive.
  • Active¬† is used¬†in preference to passive.

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