If is not the only way to talk about conditions. Unless, as long as, provided and in case each add a different meaning: an exception, a strict condition or a precaution. Choosing the right one makes you sound precise, especially at work and when you make plans.
The pattern
Unless it rains, we'll eat outside.
Take an umbrella in case it rains.
01Unless: if not, the only exception
Unless means if ... not. The verb after unless is usually positive, because the "not" is already inside the word.
Don't use unless for feelings about something that might not happen. Say "I'll be sad if you don't come," not "I'll be sad unless you come."
- We'll miss the train unless we leave now.
- Don't call after ten unless it's an emergency.
- Unless the price drops, we won't buy the house.
02As long as, provided: only on this condition
As long as, provided (that) and providing all mean "only if this happens." They sound like a deal or a rule. Provided is a little more formal, so you see it in contracts and emails from your landlord.
- You can borrow my car as long as you fill up the tank.
- Provided that you have the receipt, the store will give you a refund.
- You can work from home on Fridays as long as you answer your phone.
03In case: a precaution
In case means you do something now because something might happen later. Compare: "I'll bring a jacket in case it gets cold" (I bring it anyway) and "I'll wear a jacket if it gets cold" (only when it's cold).
In case of + noun appears on signs: in case of fire, in case of emergency.
- Save your work often in case the computer crashes.
- I wrote down the address in case my phone died.
- In case of fire, use the stairs.
04Even if, suppose, what if
Even if means the result doesn't change. Suppose and what if ask you to imagine a situation.
After all of these words, use the present to talk about the future. Never use will right after unless, as long as, provided or in case.
| Word | Meaning | Example |
|---|---|---|
| unless | if not | Unless you hurry, you'll be late. |
| as long as | only if | You can stay as long as you're quiet. |
| provided (that) | only if (formal) | Provided you pay on time, there's no fee. |
| in case | as a precaution | Bring cash in case they don't take cards. |
| even if | it doesn't matter | Even if it snows, I'm driving. |
| what if / suppose | imagine | What if we miss the flight? |
05Common mistakes
We'll go to the beach unless it doesn't rain.
We'll go to the beach unless it rains.
Unless already means if not, so the verb after it stays positive.
Take your ID in case they will ask for it.
Take your ID in case they ask for it.
Use the present, not will, after in case.
Save your work often if the computer crashes.
Save your work often in case the computer crashes.
Saving is a precaution you take now, so use in case.
You can come as long as you will be quiet.
You can come as long as you're quiet.
As long as takes the present for a future condition.