There are a few of structures in English that we call conditionals or if conditionals. The word “condition” means “situation or circumstance”. If a particular condition is true, then a particular result happens:

• • if x = 5, then 2x = 10

There are four different types of conditional sentences in English. Each expresses a different degree of probability that a situation will happen or would have happened under certain circumstances. The four conditionals are:

1. 1. Zero Conditional Sentences
   2. First Conditional Sentences
   3. Second Conditional Sentences
   4. Third Conditional Sentences

The Zero Conditional

You can make a zero conditional sentence with two present simple verbs (one in the ‘if clause’ and one in the ‘main clause’):

• • If + present simple, …. present simple.

You can use this conditional when the result will always happen. So, if water reaches 100 degrees, it always boils. It’s a fact. That is, it will happen in general, not in one particular situation. The result of the ‘if clause’ is always the main clause.

Clue: The ‘if’ in this conditional can usually be replaced by ‘when’ without changing the meaning.

For example: If water reaches 100 degrees, it boils. (It is always true, there can’t be a different result sometimes). If I eat nuts, I get sick. (This is true only for me, maybe, not for everyone, but it’s still true that I get sick every time I eat nuts)

Here are some more examples:

If people eat too much, they get fat. If you touch a fire, you get burned. People die if they don’t eat. You get water if you mix hydrogen and oxygen. Snakes bite if they are scared If babies are hungry, they cry

The First Conditional

The first conditional has the present simple after ‘if’, then the future simple in the other clause:

• • if + present simple, … will + infinitive

It’s used to talk about things which might happen in the future. Of course, we can’t know what will happen in the future, but this describes possible things, which could easily come true.

• • If it rains, I won’t go to the park.
  • If I study today, I‘ll go to the party tonight.
  • If I have enough money, I‘ll buy some new shoes.
  • She‘ll be late if the train is delayed.
  • She‘ll miss the bus if she doesn’t leave soon.
  • If I see her, I‘ll tell her.

First vs. Zero Conditional:

The first conditional describes a particular situation, whereas the zero conditional describes what happens in general.

For example (zero conditional): if you sit in the sun, you get burned (here I’m talking about every time a person sits in the sun – the burning is a natural consequence of the sitting)

But (first conditional): if you sit in the sun, you’ll get burned (here I’m talking about what will happen today, another day might be different)

First vs. Second Conditional:

The first conditional describes things that I think are likely to happen in the future, whereas the second conditional talks about things that I don’t think will really happen. It’s subjective; it depends on my point of view.

For example (first conditional): If she studies harder, she’ll pass the exam (I think it’s possible she will study harder and so she’ll pass)

But (second conditional): If she studied harder, she would pass the exam (I think that she won’t study harder, or it’s very unlikely, and so she won’t pass)

The Second Conditional

The second conditional uses the past simple after if, then ‘would’ and the infinitive:

• • if + past simple, …would + infinitive

(We can use ‘were’ instead of ‘was’ with ‘I’ and ‘he/she/it’. This is mostly done in formal writing).

It has two uses.

First, we can use it to talk about things in the future that are probably not going to be true. Maybe I’m imagining some dream for example.

• • If I won the lottery, I would buy a big house.(I probably won’t win the lottery)
  • If I met the Queen of England, I would say hello.
  • She would travel all over the world if she were rich.
  • She would pass the exam if she ever studied.(She never studies, so this won’t happen)

Second, we can use it to talk about something in the present which is impossible, because it’s not true. Is that clear? Have a look at the examples:

• • If I had his number, I would call him. (I don’t have his number now, so it’s impossible for me to call him).
  • If I were you, I wouldn’t go out with that man.

How is this different from the first conditional?

This kind of conditional sentence is different from the first conditional because this is a lot more unlikely.

For example (second conditional): If I had enough money I would buy a house with twenty bedrooms and a swimming pool (I’m probably not going to have this much money, it’s just a dream, not very real)

But (first conditional): If I have enough money, I’ll buy some new shoes (It’s much more likely that I’ll have enough money to buy some shoes)

The Third Conditional

We make the third conditional by using the past perfect after ‘if’ and then ‘would have’ and the past participle in the second part of the sentence:

• • if + past perfect, …would + have + past participle

It talks about the past. It’s used to describe a situation that didn’t happen, and to imagine the result of this situation.

• • If she had studied, she would have passed the exam (but, really we know she didn’t study and so she didn’t pass)
  • If I hadn’t eaten so much, I wouldn’t have felt sick (but I did eat a lot, and so I did feel sick).
  • If we had taken a taxi, we wouldn’t have missed the plane
  • She wouldn’t have been tired if she had gone to bed earlier
  • She would have become a teacher if she had gone to university
  • He would have been on time for the interview if he had left the house at nine

Exceptions and Special Cases When Using Conditional Sentences

As with most topics in the English language, conditional sentences often present special cases in which unique rules must be applied.

Use of the Simple Future in the If-Clause

Generally speaking, the simple future should be used only in the main clause. One exception is when the action in the if-clause will take place after the action in the main clause. For example, consider the following sentence:

The action in the if-clause is the aspirin easing the headache, which will take place only after the speaker takes them later that night.

“Were to” in the If-Clause

The verb phrase “were to” is sometimes used in conditional sentences when the likely or unlikely result is particularly awful or unthinkable. In this case, were to is used to place emphasis on this potential outcome. Consider the following sentences:

Note that the emphatic “were to” can be used to describe hypothetical scenarios in the present, future, and past.

How To Punctuatee Conditional Sentences

Despite the complex nature of conditional sentences, punctuating them properly is really simple!

Here are the rules:

• • Use a comma after the if-clause when the if-clause precedes the main clause.

• • If the main clause precedes the if-clause, no punctuation is needed.