Conditionals. APRENDER INGLES GRATIS.

“Condition” means a type of circumstance or situation.  Thus, if a particular condition is true, then it has a particular result.  This can be put simply into mathematical terms.  If A= 50 then 2A =100.
From a mathematical point of view, if we write a conditional sentence, it will be in one of the following two basic structures:

The main linking words for conditional clauses are if and unless, but even if, as/so long as, on (the) condition that, provided (that) / providing (that), supposing*, no matter who, how, when etc., can also be used.
Have a look at these examples:
             I will go out tonight even if it rains.
             You can go to the ball, as long as /so long as you come back by midnight.
             She agreed to come with us on (the) condition that she could bring her guitar.
             He could have recovered provided (that) he had stayed in bed.
In some other cases, we can substitute the conditional clause by otherwise as in this example: You’d better hurry. Otherwise, you’ll be late for your appointment. (Otherwise = if you don’t hurry).
We can also use in case or in case of + noun. This linking word is used with the present or the past to refer to a condition that could happen or not. It refers to things that we do in advanced so that we are prepared for what might come. Have a look at these two examples:
             Take an umbrella in case it rains. (Because it might rain)
             In case of accident, notify the police.
*Note the different uses of suppose and supposing:
             Suppose he comes tomorrow, will we still meet him?
             Suppose he went by train, would it be any quicker?
             Supposing he had come for an interview, would you have given him a job?
Suppose (that) / supposing (that) = what if. (and so the result clause is a question).

1. First Conditional
We use the first conditional to talk about a possibility in the future. There needs to be a real possibility that this situation could occur. For example perhaps you want to go to the beach after lunch, but the weather is a bit cloudy at the moment, and you only want to go if the sun comes out

Although we are thinking about a possibility in the future, the condition is always presented in the present simple, and the result is presented with “will + the base verb”.  Here are some other examples.

2. Second Conditional
Like the first conditional we are thinking about the future, however with the second conditional, the situation is unreal, or unlikely to occur (hypothetical).  For example you could be thinking what you would do if you had a lot of money or were a millionaire.  Most of us aren’t millionaires, but we like to think what we would do if we were. It’s like a dream.

We use the past simple in the second conditional and most commonly “would + base verb” in the result.  However, if there is less certainty in your statement or if something is possible, but you might choose not to do it, then use “could or might + base verb”.

The use of “could” indicates that there is the possibility or ability to buy a house in London, but it’s not certain that you would follow the action.  It is like saying you could afford a house in London if you were rich.

Here “might” indicates a higher level of uncertainty, you are perhaps deciding between London and another city, or thinking of spending your money on other things.
Here are some more examples.

Remember that the verb to be in the 2nd conditional always takes the form were: If I were younger...

3. Third Conditional 
We use the third conditional to talk about a situation that did not happen in the past. There is no possibility of this situation coming true, because the moment has passed.  For example: you brought a lottery ticket last week, but did not win.

We use the past perfect and most commonly “would have + base verb” to form the third conditional, however like the second conditional you can also use “could have” and “might have”.  In addition you can use “should have” if you are talking about something you regret not doing.

Using “could” here indicates that there was a possibility of buying a new car, if you could afford it. Perhaps you REALLY need a new car, and now that you know you haven’t won the lottery, that possibility is lost to you.

The use of “might” indicates that you are less in need of a new car, but you like the idea of getting a new one. Again that possibility is now lost to you.

The use of “should” indicates that the result is something necessary for you to do. Here are some more examples.


4. Zero Conditional
We use the zero conditional when we have absolute certainty of the statement (facts and general truths).  For example if you take an ice cube and put it in the sun it melts.  If it did not, you would think there was something very wrong with the world.

We use the zero conditional when we are thinking of a simple fact.  It is not past, present or future, it simply is.  But it must be a fact that always remains the same no matter what.  When can substitute if for when in the zero conditional, but the meaning doesn’t change.
Here are some examples.

5. Mixed Conditional
Compare these two sentences:
1. If you hadn’t lied to her, she wouldn’t have been angry. (It refers to the past).
2. If you hadn’t lied to her, she wouldn’t be angry now. (It refers to the present).
The change of meaning is expressed by using a different tense in the result clause. In the first sentence, we have used the 3rd conditional whereas in the second one we have used a mix of the 3rd conditional.

6. Wishes and regrets
In order to express wishes or regrets we use I wish / If only. Depending on the verb tense we use with it, we will express one thing or another. We have these four possibilities:
        a. I wish / If only + past simple: regret (something you’d like to be different now).
                              ex. I wish I had a better job.
        b. I wish / If only + past perfect: regret (about the past, nothing to do with the present)
                              ex. If only I hadn’t spent all the money.
        c. I wish / If only + could: something you wish but impossible to achieve.
                              ex. If only they cut the price.
        d. I wish / If only + would: not approving at somebody’s behaviour. (It can only be used when                there are two different subjects): ex. I wish you would stop interrupting!

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