Tricky English Words: Unless and Otherwise

Unless expresses a negative condition.

  • Unless this boy stops fooling around, he won’t learn very much.
  • Unless he takes the pencils out of his nose and ears, his teacher will get mad.

 Otherwise expresses a negative result.

  • This boy had better stop fooling around. Otherwise, he won’t learn very much.
  • He should take the pencils out of his nose and ears. Otherwise, his teacher will get mad.

Unless begins a dependent clause. This clause must be joined to an independent clause.

  • The girl will hit him unless he stops teasing her.
  • Unless he stops teasing her, the girl will hit him.

Otherwise begins an independent clause. It comes after a period or a semi-colon.

  • He ought to stop teasing her. Otherwise, the girl will hit him.
  • He should be nicer; Otherwise, he will be punished.

Practice: Look at both the grammar and the meaning to help you decide which to choose. The answers are below.

  1. It’s raining really hard right now. __________________ you don’t care about getting wet, you shouldn’t go out.
  2. Don’t text and drive. _________________, you may cause an accident.
  3. ____________________ it’s nice tomorrow, I won’t plan a picnic in the park.
  4. Don’t call your teacher by her first name ______________________ she has given you permission.
  5. You shouldn’t smoke. ________________________, you may have health problems later.
  6. ____________________ our team trains harder, we won’t win the championship.
  7. I’d better set two alarms. _______________________, I may not wake up.
  8. ____________________ you show ID, you will not be allowed to enter a bar.


1. unless
2. Otherwise
3. Unless
4. unless
5. Otherwise
6. Unless
7. Otherwise
8. Unless