What you'll learn
By the end of this lesson, you'll be able to express conditions with alternatives to "if" and in sentences where the condition is only implied.
When do I use it?
Not every condition uses "if". Common substitutes:
- unless = if not: "You'll fail unless you study." (if you don't study)
- as long as / providing (that) = on the condition that: "You can go out as long as you're back by ten."
- in case = because something might happen: "Take an umbrella in case it rains."
- otherwise / or else = if not: "Hurry up, otherwise we'll be late."
- implied — the condition is hidden in context: "I would have helped, but I didn't know." (= ...if I had known)
How do I form it?
unless + clause (= if...not) as long as / providing (that) + clause in case + clause otherwise / or else (in the result position)
- I won't come unless you invite me.
- You can borrow the car as long as you drive carefully.
- She left a note in case he returned early.
- We should leave now, otherwise we'll miss the flight.
- I didn't answer because I would have said something rude. (implied: if I had answered)
Common mistakes for Spanish speakers
"Unless" gets double-negated: "I won't go unless you don't invite me" is wrong — unless already means "if not", so only one negative. Spanish "a menos que" often pushes speakers to add the second "no". Also "en caso de que" is translated as "in case of" + noun, but with a clause it's "in case + subject + verb" ("in case it rains", not "in case of it rains"). And "otherwise" is placed to introduce the negative result, like Spanish "si no".
unless = if not (one negative only). as long as = on condition. in case = because it might happen. otherwise = if not.
Practice
Multiple Choice
B2Which sentence is correct?
Fill in the Blank
B2You can borrow the car long as you drive carefully.
Hint: 'As long as' expresses a condition: 'on condition that'.
Fill in the Blank
B2Hurry up, we'll miss the train.
Hint: 'Otherwise' introduces the negative result, meaning 'if not'.
Multiple Choice
B2What does 'Take a coat in case it gets cold' mean?
Practice Speaking
Apply what you've learned in a real conversation with AI feedback.
Level: B2