Grammar › Conditionals › Unless, as long as, provided that
Unless, as long as, provided that
These linkers add a condition, like 'if', but with a twist:
- Unless = if not / except if — I won't call unless it's urgent.
- As long as / provided that = only on this condition — You can borrow it as long as you return it.
Use the same tenses as with 'if': present simple after these words for a real future. Don't add a second 'not' after 'unless'.
The conditional linkers
| Linker | Meaning | Example |
|---|---|---|
| unless | if not / except if | I won’t go unless you come. |
| as long as | only on this condition | You can stay as long as you’re quiet. |
| provided / providing that | only if (more formal) | You’ll pass provided that you revise. |
| in case | as a precaution | Take an umbrella in case it rains. |
After all of these, use the same tenses as with if — usually the present simple for a real future.
When to use each
1. Unless (= if not)
- Unless you hurry, you’ll miss the bus. (= If you don’t hurry…)
2. As long as / provided that (a strict condition)
- You can borrow the car as long as you fill it up.
- Provided that everyone agrees, we’ll start on Monday.
3. In case (a precaution — not the same as ‘if’)
- Save your work in case the computer crashes. (do it now, as a precaution)
⚠️ Typical error:
Unless you don’t call me, I’ll be worried.→ ‘Unless’ already means ‘if not’, so drop the second negative: Unless you call me, I’ll be worried.
Common mistakes
1. Double negative after ‘unless’. unless you don’t come → unless you come.
2. Using ‘will’ after these linkers. as long as you will pay → as long as you pay.
3. Confusing ‘in case’ with ‘if’. I’ll take an umbrella if it rains (you wait to see) vs I’ll take an umbrella in case it rains (you take it now, as a precaution). Pro tip: ‘in case’ = do it in advance; ‘if’ = only do it when the condition happens.
✏️ Practice: Unless, as long as, provided that
1. ___ you hurry, you'll miss the bus.
2. You can borrow my car ___ you drive carefully.
3. Take an umbrella ___ it rains later.
4. Rewrite: 'If you don't book now, you won't get a seat.'
5. We'll start on Monday ___ everyone agrees.
6. Fix this: 'Unless you don't call, I'll worry.'
7. You can stay out late ___ you text me when you arrive.
8. I won't say anything ___ you want me to.
9. Choose the correct verb: 'Provided that you ___ on time, you can join.'
10. What does 'You'll be fine as long as you stay calm' mean?
Frequently asked questions
What does 'unless' mean?
'Unless' means 'if not' or 'except if': I won't go unless you come = I won't go if you don't come.
What is the difference between 'as long as' and 'if'?
'As long as' stresses that the condition is the only thing that matters: You can stay as long as you're quiet (= on the strict condition that…).
Is 'provided that' formal?
Yes, 'provided that' and 'providing that' are more formal than 'if' or 'as long as', common in writing and contracts.
Can I say 'unless you don't come'?
No. 'Unless' already means 'if not', so a second negative is wrong: say 'unless you come'.
👩🏫 For teachers
CEFR objectives for “Unless, as long as, provided that”:
- Can use 'unless' to mean 'if not / except if' (CEFR B1).
- Can use 'as long as' and 'provided/providing that' to state conditions.
- Can avoid double negatives after 'unless'.
⬇︎ Download the Lesson Pack (PDF)
Printable worksheet + answer key + one-page summary. Free to use and print in class with attribution. Join the newsletter for new packs and cheat sheets.