Conditionals: B1 Exercises

Every answer with the reason behind it. Read the explanation for the ones you got right as well — that is where you find out whether you were right for the right reason.

Multiple choice questions — answers

1. If you heat water to 100°C, it ___. → boils

Zero conditional: a fact that is always true takes the present simple in both halves, not will.

2. If the fire alarm ___, leave the building immediately. → rings

The result here is an imperative, but the if clause still takes the present simple.

3. If I ___ you, I would tell her the truth today. → were

The fixed advice pattern is if I were you. Careful English keeps were for every person in the second conditional.

4. We will cancel the hike ___ the storm passes overnight. → unless

Unless means 'except if': the hike is cancelled in every case but that one.

5. I will ring you ___ I land, so keep your phone switched on. → when

The landing is certain, so when is right. If would suggest the plane might never arrive.

6. If I had a garden, I ___ grow my own vegetables. → would

Second conditional: an imagined present takes would plus the base verb.

7. If she ___ the offer, she will regret it later. → refuses

First conditional: the if clause stays in the present simple even though it points at the future.

8. Which of these is a second conditional? → If he called, I would answer.

Past simple in the if clause plus would in the result is the second conditional — an unreal present, not a past event.

9. If you ___ the icon twice, the file opens. → click

A machine behaves the same way every time, so this is the zero conditional: present simple throughout.

10. If they offered me the post in Berlin, I ___ probably take it. → would

Offered signals an imagined situation, so the result clause needs would rather than will.

11. In the polite request 'If you will wait a moment', will means ___. → willingness

Will is allowed inside an if clause when it means 'be willing to'. That is the exception to the no-will rule, and it is a request, not a prediction.

12. If I ___ enough money saved, I would move abroad next year. → had

The speaker does not have the money, so the unreal present takes the past simple in the if clause.

13. ___ you book early, the prices go up sharply. → If you don't

Unless already carries the negative, so unless you don't would be a double negative. If you don't is the clean version.

14. If the meeting ___ late, I might miss my last train. → finishes

A real future possibility: present simple after if, and might in the result because the outcome is not certain.

15. We ___ go to the coast on Sunday if the forecast improves. → might

Might replaces will in a first conditional when the speaker means 'possibly' rather than 'definitely'.

16. If I were taller, I ___ reach the top shelf without a stool. → could

Could is the second-conditional form of can: an ability that does not exist in reality.

17. Which sentence sounds natural to a native speaker? → If it snows, we will stay at home.

Present simple after if, will in the result. Mixing a past if clause with will is the pattern to avoid.

18. If nobody ___ the door, the parcel goes back to the depot. → answers

This is standard company procedure rather than one occasion, so the zero conditional fits: present simple in both clauses.

19. 'If I knew the answer, I would tell you' tells us that the speaker ___. → does not know the answer

The second conditional describes an unreal present, so the if clause is false at the moment of speaking.

20. If we ___ this minute, we would still arrive after the interval. → left

Left plus would marks the situation as hypothetical — the speaker is not actually proposing to go.

Fill-in-the-blank questions — answers

1. If you mix blue and yellow paint, you ___ green. → get

Zero conditional: an unchanging result takes the present simple in both halves.

2. If I were rich, I ___ travel the whole world. → would

The second conditional pairs a past-simple if clause with would in the result.

3. ___ you hurry, you will miss the last ferry. → Unless

Unless means 'if not', so it replaces a negative if clause without adding another negative.

4. Ice ___ quickly if you leave it in direct sunlight. → melts

A physical law is always true, so the zero conditional uses the present simple.

5. If I had her number, I ___ call her this evening. → would

The speaker does not have the number, so the result clause is hypothetical and takes would.

6. I will let you know as soon as I ___ the results. → get

As soon as behaves exactly like if here: the clause stays in the present simple.

7. If she ___ me to lend her the car, I would have to refuse. → asked

The past simple after if marks the request as imagined rather than actual.

8. If you never water houseplants, they ___. → die

A general consequence, true every time, so the zero conditional applies.

9. We would buy that flat if it ___ quite so expensive. → weren't

The unreal present uses a past form; were is the careful choice after it in this pattern.

10. If the train is delayed again, I ___ take a taxi instead. → will

First conditional: a real future possibility, so will plus the base verb in the result.

11. If I ___ how to drive, my life would be far simpler. → knew

Knew signals an unreal present — the speaker cannot drive.

12. Water freezes ___ the temperature drops below zero. → when

When suits a certainty; both when and if work in a zero conditional about physical law.

13. If you press this key, the screen ___ off automatically. → switches

The machine does the same thing every time, so the present simple is correct in both clauses.

14. If I ___ you, I would take the earlier flight. → were

If I were you is the fixed advice formula; were is preferred in careful writing.

15. She would be furious if she ___ what he said about her. → heard

The past simple after if marks the situation as one that has not happened.

16. ___ it rains on Saturday, the match will be postponed. → If

A real, uncertain future event, so if plus the present simple opens a first conditional.

17. If we do not reserve a table, we ___ have to wait an hour. → will

The result of a real future condition takes will plus the base verb.

18. If I could speak Japanese, I ___ apply for the Tokyo office. → would

Could speak sets up an unreal present, so the result clause needs would.

19. The alarm ___ whenever anyone opens that window. → sounds

Whenever makes this a repeated, automatic result: zero conditional, present simple.

20. What would you do if your laptop ___ stolen at the airport? → were

An imagined misfortune, so the if clause takes a past form even though it refers to the future.

Sentence structure: word ordering — answers

1. State a scientific fact with the zero conditional. → If you freeze water, it becomes ice.

State a scientific fact with the zero conditional.

2. Give advice using the fixed were formula. → If I were you, I would apologise.

Give advice using the fixed were formula.

3. Attach a single escape condition with unless. → We will leave unless the rain stops.

Attach a single escape condition with unless.

4. Pair a real condition with an instruction. → If she calls, tell her I am busy.

Pair a real condition with an instruction.

5. Put the imagined result first and the condition second. → I would buy a boat if I were rich.

Put the imagined result first and the condition second.

6. Describe how a device always behaves. → If the light turns red, the machine stops.

Describe how a device always behaves.

7. Ask a hypothetical question about a travel problem. → What would you do if you lost your passport?

Ask a hypothetical question about a travel problem.

8. Use a softer result than will. → If we hurry, we might catch the train.

Use a softer result than will.

9. Explain why someone is staying silent. → She would tell you if she knew the answer.

Explain why someone is staying silent.

10. State a law of physics in five words after if. → If you heat metal, it expands.

State a law of physics in five words after if.

11. Open the sentence with the negative conjunction. → Unless you apply today, the offer expires.

Open the sentence with the negative conjunction.

12. Imagine owning something you do not have. → If I had a car, I would drive there.

Imagine owning something you do not have.

13. Give an instruction with the condition second. → Call me if anything goes wrong.

Give an instruction with the condition second.

14. Leave a polite instruction for a delivery. → If the parcel arrives, please sign for it.

Leave a polite instruction for a delivery.

15. Reassure somebody by imagining yourself in their place. → I would not worry if I were in your position.

Reassure somebody by imagining yourself in their place.

16. Ask about a hypothetical pay rise. → If they offered more money, would you accept?

Ask about a hypothetical pay rise.

17. Explain an automatic mechanism. → The door locks automatically if you close it.

Explain an automatic mechanism.

18. Predict one real consequence of tomorrow's weather. → If it snows tonight, school will be cancelled.

Predict one real consequence of tomorrow's weather.

19. Suggest an improvement he has not made. → He would be happier if he changed jobs.

Suggest an improvement he has not made.

20. Pass on a message conditionally. → If you see Anna, give her my regards.

Pass on a message conditionally.