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Interactive Grammar: Unless and Conditionals

Use 'unless' and 'if … not' in conditional sentences to express exceptions, warnings, and negative conditions.

Grammar Explanation · Authentic Examples · Practice Exercises

Lesson progressNot started
Duration
~64 min
Exercises
43
Level
Intermediate

Overview

Use 'unless' and 'if … not' in conditional sentences to express exceptions, warnings, and negative conditions.

Unless = If … not

  • structureUnless + present simple, future simple
  • meaningUnless = if … not: Unless you hurry = If you don't hurry.
  • exampleUnless you study, you will fail.
  • exampleI won't go unless you come with me.

Important rules

  • After unless, use present simple (not 'will'): Unless you hurry
  • Unless is never used with a negative: ❌ Unless you don't study.
  • Compare: unless (if not) ≠ even if (regardless)

Common Mistakes

  • Unless you won't hurry. → ✅ Unless you hurry.
  • Unless she doesn't study, she'll fail. → ✅ Unless she studies, she'll fail.
  • Unless if you register. → ✅ Unless you register. (no 'if')

When to use

Rules & policies

Unless you have a ticket, you cannot enter.

Conditions

Unless the terms improve, we won't sign.

Academic warnings

Unless you cite sources, marks will be deducted.

Conversations

Unless you tell me, I can't help you.

Multiple Choice

Choose unless or if … not to complete each sentence correctly

Multiple Choice15 questions
1I won't go you come with me.
2'Unless' means .
3 you study, you will fail.
4I won't go unless you with me.
5Which is incorrect?
6The meeting will be cancelled we reach a quorum.
7She come unless she finishes her work first.
8'Unless you hurry' = .
9Which sentence uses 'unless' correctly?
10After 'unless', we use .
11 you have a reservation, the restaurant may be full.
12He will not succeed he works harder.
13'You won't get the job if you don't prepare' = You won't get the job .
14Which use is NOT correct for 'unless'?
15She will be upset you apologise immediately.

Fill in the Blanks

Complete with unless or if … not

Fill in the Blanks10 questions
1(Unless/If not)you study, you won't pass.
2I won't go(unless/if not)you come with me.
3He(unless/won't go unless)he gets better, he won't play.
4(Unless/If)there is rain, we will go out.
5She will feel rejected(unless/if)you apologise now.
6The project will fail(unless/although)we get more funding.
7(Unless/If not)it is an emergency, do not call after nine.
8I will help you(unless/if)you don't want me to.
9They won't attend(unless/although)the venue changes.
10(Unless/Because)you book early, you may not get a seat.

Transform the Sentences

Rewrite using 'unless' instead of 'if … not'

Transform8 questions

1If you don't leave now, you will miss the train. → Use 'unless'

2If she doesn't apologise, he will be upset. → Use 'unless'

3If they don't act quickly, the problem will worsen. → Use 'unless'

4If you don't have a ticket, you cannot enter. → Use 'unless'

5If he doesn't revise, he will fail. → Use 'unless'

6I won't accept the offer if it doesn't improve. → Use 'unless'

7The project will fail if we don't get more funding. → Use 'unless'

8She won't agree if the terms don't change. → Use 'unless'

Fix the Errors

Correct the mistake in each 'unless' sentence

Error Fix10 questions

1Unless you won't hurry, you'll be late.

2I won't come unless if you invite me.

3Unless she doesn't study, she'll fail.

4He won't come unless he will get an invitation.

5Unless you not leave now, you'll miss the bus.

6She unless studies hard, she won't pass.

7The event will be cancelled unless if it rains.

8Unless she doesn't apologise, he stays angry.

9I can't help you unless you don't ask me.

10Unless you won't register, you can't attend.

Frequently Asked Questions

What does this lesson on conditionals cover?

Use 'unless' and 'if … not' in conditional sentences to express exceptions, warnings, and negative conditions.

Which CEFR level is this lesson designed for?

This lesson is designed for Intermediate (B1) learners and forms part of the Conditionals section on Grammartier.

What is the best approach for studying this grammar topic?

Start with the definition, then study the examples carefully to understand how the pattern works in context. Practise identifying the structure in authentic sentences before producing your own — this recognition-first approach builds a strong foundation for accurate, confident use.

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