unless

Meanings

1. 1conjunction

   Except if; used to introduce the only condition that would stop something from happening.

   Grammar: Introduces a clause that states an exception. It already carries a negative meaning, so do not add 'not' inside the same clause.

   Patterns

   • unless + clause
   • unless something happens

   I won't go to the party unless you come with me.

   Unless it rains, we'll have the picnic in the park.

   You can't enter the building unless you show your ID.

2. 2conjunction

   Used to add a condition that makes a statement true only in all other cases.

   Grammar: Often used after a negative main clause, but it can also follow a positive one to set a limit.

   Patterns

   • unless otherwise stated
   • unless and until

   The offer is valid unless it is withdrawn before the deadline.

   Unless I'm mistaken, the meeting is on Tuesday.

   We'll proceed unless we hear otherwise from the client.

Common combinations

unless otherwise stated

All prices include tax unless otherwise stated.

unless and until

The policy remains in effect unless and until it is changed.

unless I'm mistaken

Unless I'm mistaken, this is the first time we've met.

unless something changes

Unless something changes, we'll miss the deadline.

Synonyms and how they differ

if not

Similar meaning, but 'if not' can be ambiguous and is less common at the start of a sentence.

except if

More literal and emphatic; 'unless' is smoother and more usual in everyday speech.

Commonly confused: unless or if?

Practice

Make it your own

Write a sentence using “unless”, then check it and compare it with the examples above.

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