A conditional sentence has an if clause and a main clause. Zero: if + present, present (facts). First: if + present, will (real future). Second: if + past, would (unreal present). Third: if + past perfect, would have (unreal past). Unless means "if not". The answer key is at the end.
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Conditional Sentences Worksheet with Answers
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A. Which conditional?
Write zero, first, second or third.
- If you heat ice, it melts.
- If it rains tomorrow, we will cancel the picnic.
- If I were a bird, I would fly to Kerala.
- If she had studied, she would have passed.
- If you mix red and blue, you get purple.
- If Ravi wins the match, his team will celebrate.
- If I had a car, I would drive to Jaipur.
- If we had left earlier, we would have caught the train.
B. Complete the sentence
Fill in the blank with the correct form of the verb in brackets. Some answers need more than one word. Use will or would where a modal is needed.
- If it rains tomorrow, I __________ (stay) at home.
- If I __________ (be) rich, I would buy a big house.
- If you had called me, I __________ (help) you.
- Water __________ (boil) if you heat it to 100 degrees.
- If she __________ (not hurry), she will miss the bus.
- If Meena had known the answer, she __________ (tell) us.
- If I __________ (have) more time, I would learn the guitar.
- If you __________ (study) hard, you will pass.
- If he had taken the medicine, he __________ (feel) better yesterday.
- If they __________ (not leave) now, they would be late.
C. Unless
Rewrite each sentence with the word in brackets. Keep the meaning.
- If you do not hurry, you will miss the train. (Unless)
- If you don't study, you will not pass. (Unless)
- Unless it rains, we will play cricket. (If)
- I will not go if she does not invite me. (unless)
D. Choose the correct form
Circle the correct word or phrase.
- If I (would have / had) known, I would have told you.
- If it (will rain / rains), we will stay indoors.
- If he (studies / studied) harder, he would get better marks.
- You will fail (if / unless) you work hard.
E. Correct the mistakes
Each sentence has one mistake. Write the sentence correctly.
- If I will see him, I will tell him.
- If she would have asked, I would have helped.
Answer Key
A. Which conditional?
- zero
- first
- second
- third
- zero
- first
- second
- third
B. Complete the sentence
- will stay
- were (or was)
- would have helped
- boils (or will boil)
- does not hurry (or doesn't hurry)
- would have told
- had
- study
- would have felt
- did not leave (or didn't leave)
C. Unless
- Unless you hurry, you will miss the train.
- Unless you study, you will not pass.
- If it does not rain, we will play cricket. (or doesn't rain)
- I will not go unless she invites me.
D. Choose the correct form
- had
- rains
- studied
- unless
E. Correct the mistakes
- If I see him, I will tell him.
- If she had asked, I would have helped.