IF + DOES, DOES1. If is used to state general rules.
If + present simple tense, present simple tense
B. The 1st conditional
If + present simple tense, will + bare infinitive
3. When we talk about an event that will take place in the future, we can use if or when.
I am flying to the States tonight. I'll give you a ring if I can find a phone.4. In a sentence with an if-clause we can use the imperative, or other modal verbs, instead of will + infinitive
(The speaker is not sure if he will be able to find a phone or not.)
I am flying to the States tonight. I'll give you a ring when I get there.
(The speaker has no doubt that the plane will arrive safely.)
If you hear from Susan today, tell her to ring me.5. 1st conditional is usually used in such cases:
If the traffic is bad, I may get home late.
Note. We say the traffic but a traffic jam
6. If and unless
Unless means the same as if ... not. It always refer to the conditional part of the sentence and not the result part of the sentence:
If he doesn't get here soon, we will have to start the meeting without him.We often use not + unless, which means only ... if, when we want to emphasize a condition:
Unless he gets here soon, we will have to start the meeting without him.
They will only sign the contract if we give them an additional discount.7. If and in case
They won't sign the contract unless we give them an additional discount.
We use in case to talk about precautions we will take before a problem happens. We use if to talk about what we will do after a problem happens:
We are going to insure the shipment in case the goods get damaged in transit.Note that that in sentence with in case, we often use going to rather than will because we are often talking about something that we have already decided to do.
(We will take our insurance first; the problem may or may not happen afterward.)
If the goods get damaged in transit, we'll make a claim.
(The damage may happen, and we will make a claim afterward.)
8. Provided that vs as long as, etc.
We can use provided that/providing, as long as, and so long as when we want to emphasize condition. Provided that and as long as mean if and only if (providing and so long as are a little less formal):
I will agree to these conditions provided that they increase my salary.9. So that
(I will only agree if they give me more money.)
The strike will be successful as long as we all stay together.
(It will only succeed if we all stay together.)
We use so that to say what the result or purpose of an action will be:
I'll take a credit card so that we don't run out of money.
(The credit card will stop us from running out of money)
D. 2nd conditional
If + past tense, would + infinitive
If I knew her number, I would send her a fax.COMMON MISTAKE. We do not use would in the if part of the sentence.
I would send her a fax if I knew her number.
11. This form refers to present or future time.
If these machines were not so expensive, we would buy them.The first two sentences refer to present situation, and imagining a situation that is different from the reality. In the third we are talking about a possible event in the future, but using second conditional we make it clear that we do not really think it will happen.
If we hired a lawyer, we would recover our debts more easily.
If I lost my job tomorrow, I would move to London to find the same kind of job.
12. 2nd conditional is usually used in such cases
If we think that future event is reasonably likely, we use first conditional
If the market grows at 7% a month, it will involve new investment rapidly.If we are talking about an event that is unlikely or impossible, we use the second conditional
If I had as much money as Bill Gates of Microsoft, I would retire.14. Variation
It is also possible to use might and could instead of would
If we received credit, we could expand much more rapidly.In the if-clause , we can use were instead of was. This is very common when we give advice using the expression If I were you ...
If I were you, I would have another look through those figures.
E. 3rd conditional
If + past perfect tense, would + present perfect
When we use the 3rd conditional we are imagining the opposite situation. If what actually happened was negative, we use a positive form. If what actually happened was positive, we use a negative form:
If my client had given me her fax number, I wouldn't have had to post a letter to her.17. Mixed conditionals
If I'd known it was a formal party, I wouldn't have gone wearing jeans and a jumper.
If I had not been in Amsterdam at the last RIPE meeting, I would not have met Esther Dyson and I wouldn't have known she speaks Russian.
If we talk about a past action and its result in the present we use if + past perfect and would not + infinitive:
If he hadn't done well on the training courses, he wouldn't be a Project leader now.
|1999. Yuri Demchenko.