First Conditional Sentences Rules
- If I see him, I will tell him.
- If I will see him, I will tell him. (Incorrect)
We use the ‘if’ clause + the present simple tense. This clause is the condition.
We use the future simple tense, ‘will + infinitive’ to indicate the result of the condition.
We use the first conditional to speak about a possible situation in the future.
- If I win the lottery, I will buy a new house.
I think I have a possibility to win because perhaps I have bought many lottery tickets.
To make the negative of the first conditional just put the negative of the present simple on the ‘if’ clause and the negative of ‘will’ on the result of the condition clause. Example:
- If I don’t go, I won’t see him.
- If I don’t go, I won’t see him.
- If he doesn’t arrive soon, we won’t have time to catch the 9.30 train.
We use the same structure with: When -as soon as – before – after – in case – until – unless Example:
- I’ll see him, when I go to the airport.
- I’ll call you, as soon as I arrive.
- I’ll text you before I leave.
- After she goes, I’ll start cooking.
We can use the following modal auxiliary verbs although the degree of possibility varies according to which one we use.
A modal auxiliary modifies the meaning of the verb. Modals are a nightmare for learners of English. This is because they are never ‘black’ and ‘white’. Their meanings come in many ‘shades of grey.’ Here is a list of the options: must – can – could – may – might – should. Let’s take a look at some examples:
- I will go if he calls me.
‘Will’ expresses a certainty
- I must go if he calls me.
‘Must’ expresses a personal obligation from the speaker (in this example)
- I can go if he calls me.
‘Can’ expresses either permission from a third party or the fact that you are free from other commitments.
- I might go if he calls me.
‘Might’ expresses a 50/50 possibility. You haven’t decided yet.
- I may go if he calls me.
‘May’ is similar to might, the possibility is slightly less. It is also more formal than ‘might’.
- I should go if he calls me.
I feel a mild obligation.
- You should go if he calls you.
Someone is recommending that you go or giving you his/her personal opinion.
To form the question, we invert the subject with the modal auxiliary. For the negative we add ‘not’. Example:
- Should I go, if he calls me?
- You shouldn’t go if he calls you?
- I might not go if he calls me. (We do not contract ‘might’ in the negative).
In the question ‘might’ is not very common.
- Might I go? (Nowadays it is rarely used. In old English it was more common).
We use ‘may’ to ask questions but only for permission.
- May I go if he calls me? (I am asking permission)
- Must I go if he calls me? (This denotes the idea that you really do not want to go)
Second Conditional Sentences Rules
- If I would go to London, I would visit Trafalgar Square. (incorrect)
- If I went to London, I would visit Trafalgar Square.
After the ‘if’ clause (the condition) we use the past simple.
We use ‘would + infinitive’ for the result of the condition.
We use the second conditional to speak about a hypothetical situation.
- If I won the lottery, I would buy a new house.
I am dreaming of winning the lottery, I probably haven’t even bought a lottery ticket. More examples:
- If I had a phone, I would phone you every day. = I don’t have a phone so I cannot phone you every day.
- If we had a camera, we could take photographs. = We don’t have a camera so we can’t take photographs.
To make the second conditional negative, just put the negative of the past simple after the ‘if’ clause and the negative of ‘would’ on the result of the condition clause. Example:
- If I didn’t live in London, I wouldn’t speak English so well.
To form the question, invert ‘would’ with the subject and put a question word before ‘would’. Example:
- What would you do if you won the lottery?
- Where would you go if you won the lottery?
- If you could have dinner with a famous person, who would you choose?
Third Conditional Sentences Rules
- If I would have been there, I would have helped you. (Incorrect)
- If I had been there, I would have helped you.
There are often errors in forming the third conditional. In the first example, that is, the one which is wrong, there is double use of ‘would’.
In the third conditional, is to remember that after the ‘if’ clause, that is, the condition, we use the past perfect, and on the result of condition clause, ‘would have + past participle’ of the verb.
The third conditional is used for something which did not happen in the past. Example: I saw you yesterday but you didn’t see me.
- If I had seen you I would have said hello.
To form the negative put ‘not’ after the auxiliary verb ‘had’ and ‘not’ after the modal auxiliary ‘would’. Example: I was late for work yesterday because I overslept. (= sleep too much)
- If I hadn’t overslept, I wouldn’t have been late for work.
To form the question we invert ‘would’ with the subject and add a question word where necessary. Example:
- Would you have come to the party if you had known about it?
- What would you have done, if you had been me?
- Where would you have gone, if you hadn’t come here?
Mixed Conditional Sentences Rules
A very commonly used conditional that many grammar books tend to overlook is the ‘mixed conditional. It is a cross between the third conditional and the second. Example:
- If I had studied more (the condition is in the past) I would be a doctor (the result of the condition is in the present.
Other examples: I wasn’t born in Italy (past) I am not Italian. (present)
- If I had been born in Italy, I would be Italian. (now)
He lost his job. (past) He is unemployed. (present)
- If he hadn’t lost his job, he wouldn’t be unemployed (now).
Thanks for reading about “conditional sentences rules”.