Conditionals

This page has information about conditionals, in particular the three common patterns.

A conditional sentence is a sentence containing the word if. There are four common types* of conditional sentence:

  • 0. if clause → present simple : main clause → present simple
    • If you let go of an object, it falls.
    • If it rains, the ground gets wet.
    • If a stone is dropped into water, it sinks.
  • 1. if clause → present simple : main clause → future (will)
    • If you help me, I will help you.
    • If I win the lottery, I will buy a new car.
    • If it snows tomorrow, we will go skiing.
  • 2. if clause → past simple : main clause → would
    • If you helped me, I would help you.
    • If I won the lottery, I would buy a new car.
    • If it snowed tomorrow, we would go skiing.
  • 3. if clause → past perfect : main clause → would have
    • If you had helped me, I would have helped you.
    • If I had won the lottery, I would have bought a new car.
    • If it had snowed yesterday, we would have gone skiing.

Of course, it is possible to start conditional sentences with the main clause:

  • An object falls if you let go of it.
  • I will buy a new car if I win the lottery.
  • I would buy a new car if I won the lottery.
  • I would have bought a new car if I had won the lottery.

English speakers choose one of the four conditional structures listed on this page as follows:

Zero Conditional - to express a scientific truth or a situation that is always true

  • If you drop oil into water, the oil floats.
  • If I see a black cat on the street, I make a wish.
  • She feels very happy if someone likes her picture on Instagram.

First Conditional - to express a simple statement of fact or intent

  • I will buy a new car if I win the lottery.
  • I will go home if you don't stop criticizing me.
  • You will fail your exams if you don't start working harder.
  • She will lose all her friends if she continues to talk about them behind their backs.

Second Conditional - to refer to a present unreal situation or to a situation in the future that the speaker thinks is unlikely to happen

  • If I had a lot of money, I would buy a new car. (but I don't have a lot of money - unreal situation )
  • If I were you, I would tell him you're sorry. (but I am not you - unreal situation )
  • If I won the lottery, I would buy a new house. (but I don't expect to win the lottery - unlikely to happen )
  • If it snowed tomorrow, we would go skiing. (but I don't have much hope that it will snow )

Third Conditional - to refer to the past and situations that did not happen

  • If it had snowed yesterday, we would have gone skiing. (but it didn't snow, so we didn't go skiing )
  • If you had studied harder, you would have passed your test. (but you didn't study hard, so you didn't pass your test )
  • If I had known that, I would have told you. (but I didn't know, so I didn't tell you )
  • If she hadn't been driving slowly, she would have had an accident. (but she was driving slowly, so she didn't have an accident )

Here is a page that shows how to construct conditional three sentences from questions. More The link is to a .pdf file. The examples are based on predicting alternative realities in the case of the space shuttle disaster in 1986.


* Important Note: I have explained English conditional grammar with the four common clause patterns as above since the conditional is often taught this way in language classrooms or online grammar resources.

But the way native speakers of English express conditions (use if-statements ) is very much more varied than the four common combinations of tenses exemplified on this page. And it might in fact be more helpful to distinguish just two major categories:

  • real conditionals: constructions in which the condition always, will probably, or might happen (i.e. zero, first and second conditional above)
  • unreal conditionals: constructions in which the condition is not true or did not happen (i.e. the second and third conditional above)

At any rate, learners should consult a good grammar reference work for a deeper understanding of this complex aspect of English grammar.

More resources on the conditional

There are several interactive quizzes on the conditional in the Verb grammar: Miscellaneous drop-down menu on the Grammar index.