First Conditional Sentences Formula and Rules with Examples

What are the First Conditional Sentences (Definition)

The first conditional sentences, also called the possible conditional, use the present simple tense in the if clause to describe the condition and the future simple tense in the main clause to describe a probable result of the condition. The first conditional describes a real or very likely situation in the present or future.

First Conditional Sentences Formula and Uses with Examples

First Conditional Sentences Formula/Structure

There are several variations of the first conditional structure in both the if clause and the main clause.

Must Read: Zero Conditional Sentences

If + present simple tense, will + infinitive

If + present continuous, ……


  • If you are still studying grammar, I will share with you some new websites.
  • If you are searching for your phone, you’ll find it in my room.

If + present perfect, …


  • If he has finished his study, he can go with us.
  • If you have written the post, I’ll publish it.
  • If she has a qualification in English, she might get a good job.

If + present perfect continuous, …

First Conditional Rules and Uses

Instead of the above structures with future simple in the main clause, we have the following variations of the main clause with present simple tense in the if clause.

To describe how possible the condition described in the if clause, we may have may/might in the main/result clause

If + present simple tense + may/might

The present simple tense in the if-clause may be followed by ‘may’, or ‘can’ that gives permission or describes ability in the result clause.


  • If you pick that, it might break.
  • If + present simple tense + may/can
  • If it stops raining, I can go to school.
  • If they hurry, they may catch the bus.
  • If we hurry, we will catch the train.
  • I may go if he calls me.

The present tense in the if-clause may be followed by should, must, or any other expression that expresses request, command, or advice, etc.

If + present simple tense + must/should………


  • If the students want to get high marks had better study hard.
  • If the students want to get high marks, study hard.
  • If you meet Ahmad tomorrow, could you give him this money?
  • If he phones again, you must answer him.
  • If she contacts you, you should inform her.

First Conditional Sentences Examples

  • If you eat all these sweets, you will feel terrible.
  • He will lend you if he has enough money.
  • If she studies hard, she will pass the paper with good marks.
  • If I save some money, I will buy a new car.
  • If a student asks me, I will answer him.
  • If she hurries, she will catch the bus.

The first conditional is also used to make promises or warnings and to give a command.


  • If you don’t come today, I’ll never meet you again.
  • If you are sick, go to the hospital!

Negative and Interrogative Sentences

The negative of the first conditional can be formed by making the tense negative in the if-clause. The question can be created in the first conditional when the subject and modal auxiliary verb are inverted.

  • If we do not go, we will not catch them.
  • I will not attend the meeting if he doesn’t invite me.
  • Men die if they do not eat.
  • If I come home early, may I go to the stadium?
  • If we come, will she teach us English?

How to Differentiate Between Zero and First?

So far, we have discussed both the zero and the first conditional and explained the concept with several examples. So, the question that arises here is how the zero and first are different from each other, and why do we choose one over another? To explain the difference, let’s take some examples.


  • Zero Conditional: If pour oil on the water, it floats.
  • First Conditional: If pour oil on the water, it will float.

In this example, the first sentence is the zero conditional, and the second one is the first conditional. Both these sentences are correct. But it does change the meaning a little by choosing the zero or the first conditional. The difference between these two sentences is that the first sentence states a general fact, i.e., the situation described in the first sentence is true at any moment and anywhere.

When we use the first conditional for the same situation, we tell someone about a possible result based on the current situation. So, it’s like we are giving advice or warn someone about the present situation.


  • Zero Conditional: When the sun sets, it gets dark.
  • First Conditional: When the sun sets, it will get dark.

We are again using the zero conditional to describe a general fact. It is true everywhere when the sun sets; it gets darker.

But when we are using the first conditional, we remind someone about the situation that it will get dark in a few hours. So, the person needs to take a light with himself, or you are warned to return soon before it gets darker.


  • Zero: If he doesn’t come, I’m angry.
  • First: If he doesn’t come, I’ll be angry.

Suppose these two sentences describe my friend routine who always comes to my home and we study together.

We have used the zero conditional in the first sentence because it describes the situation that happens to me a lot. He often doesn’t come, and every time I am angry.

In the second case, the first conditional is used because I am talking about a specific day on which he doesn’t come. So, I am not talking about his general habit. I am not always angry with him, but I’m talking about it right now at this moment.

In simple words, the zero conditional always describes a general truth, and the first conditional describes a warning or reminder to someone about a specific situation.

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