GRAMMAY THEORY

CONDITIONAL SENTENCES

Conditional sentences are sentences expressing factual implications, or hypothetical situations and their consequences. They are so called because the validity of the main clause of the sentence is conditional on the existence of certain circumstances, which may be expressed in a dependent clause or may be understood from the context.

A full conditional sentence (one which expresses the condition as well as its consequences) therefore contains two clauses: the dependent clause expressing the condition, called the protasis; and the main clause expressing the consequence, called the apodosis. An example of such a sentence (in English) is the following:

    If it rains, the picnic will be cancelled.

Here the condition is expressed by the clause "If it rains", this being the protasis, while the consequence is expressed by "the picnic will be cancelled", this being the apodosis. (The protasis may either precede or follow the apodosis; it is equally possible to say "The picnic will be cancelled if it rains".) In terms of logic, the protasis corresponds to the antecedent, and the apodosis to the consequent.

Languages use a variety of grammatical forms and constructions in conditional sentences. The forms of verbs used in the protasis and apodosis are often subject to particular rules as regards their tense and mood. Many languages have a specialized type of verb form called the conditional mood – broadly equivalent in meaning to the English "would (do something)" – for use in some types of conditional sentence

TYPES OF CONDITIONALS

              

First conditional

"First conditional" refers to predictive conditional sentences (see above section); here, normally, the condition is expressed using the present tense and the consequence using the future:

If you make a mistake, someone will let you know.

Second conditional

"Second conditional" refers to the pattern where the condition clause is in the past tense, and the consequence in conditional mood (using would or, in the first person and rarely, should). This is used for hypothetical, counterfactual situations in a present or future time frame (where the condition expressed is known to be false or is presented as unlikely).

If I liked parties, I would attend more of them.

If it were to rain tomorrow, I would dance in the street.

The past tense used in the condition clause is historically the past subjunctive; however in modern English this is identical to the past indicative except in certain dialects in the case of the verb be (first and third person singular), where the indicative is was and the subjunctive were. In this case either form may be used (was is more colloquial, and were more formal, although the phrase if I were you is common in colloquial language too):

If I (he, she, it) was/were rich, there would be plenty of money available for this project.

Third conditional

"Third conditional" is the pattern where the condition clause is in the past perfect, and the consequence is expressed using the conditional perfect. This is used to refer to hypothetical, counterfactual (or believed likely to be counterfactual) situations in the past

If you had called me, I would have come.

Mixed conditionals

"Mixed conditional" usually refers to a mixture of the second and third conditionals (the counterfactual patterns). Here either the condition or the consequence, but not both, has a past time reference:

If you had done your job properly, we wouldn't be in this mess now.

If we were soldiers, we wouldn't have done it like  


                  ZERO CONDITIONAL

                           

Zero Conditional

for certainty

If you heat ice, it melts.

We use the so-called zero conditional when the result of the condition is always true, like a scientific fact.
Take some ice. Put it in a saucepan. Heat the saucepan. What happens? The ice melts (it becomes water). You would be surprised if it did not.

if	condition	result
	Present Simple	Present Simple
If	you heat ice,	it melts.

Notice that we are thinking about a result that is always true for this condition. The result of the condition is an absolute certainty. We are not thinking about the future or the past, or even the present. We are thinking about a simple fact. We use the Present Simple tense to talk about the condition. We also use the Present Simple tense to talk about the result. The important thing about the zero conditional is that the condition always has the same result.
Look at these example sentences:

if	condition	result
	Present Simple	Present Simple
If	I miss the 8 o'clock bus,	I am late for work.
If	I am late for work,	my boss gets angry.
If	people don't eat,	they get hungry.
If	you heat ice,	does it melt?

result	if	condition
Present Simple		Present Simple
I am late for work	if	I miss the 8 o'clock bus.
My boss gets angry	if	I am late for work.
People get hungry	if	they don't eat.
Does ice melt	if	you heat it?

Form

In zero conditional sentences, the tense in both parts of the sentence is the simple present.

If clause (condition)	Main clause (result)
If + simple present	simple present
If this thing happens	that thing happens.

As in all conditional sentences, the order of the clauses is not fixed. You may have to rearrange the pronouns and adjust punctuation when you change the order of the clauses, but the meaning is identical. In zero conditional sentences, you can replace "if" with "when", because both express general truths. The meaning will be unchanged.

Examples

• If you heat ice, it melts.
• Ice melts if you heat it.
• When you heat ice, it melts.
• Ice melts when you heat it.
• If it rains, the grass gets wet.
• The grass gets wet if it rains.
• When it rains, the grass gets wet.
• The grass gets wet when it rains.

Function

The zero conditional is used to make statements about the real world, and often refers to general truths, such as scientific facts. In these sentences, the time is now or always and the situation is real and possible.

Examples

• If you freeze water, it becomes a solid.
• Plants die if they don't get enough water.
• If my husband has a cold, I usually catch it.
• If public transport is efficient, people stop using their cars.
• If you mix red and blue, you get purple.

The zero conditional is also often used to give instructions, using the imperative in the main clause.

Examples

• If Bill phones, tell him to meet me at the cinema.
• Ask Pete if you're not sure what to do.
• If you want to come, call me before 5:00.
• Meet me here if we get separated.

                         

                                     STRUCTURE
                              
                   
                                      
                       

                  First Conditional

for real possibility

If I win the lottery, I will buy a car.

We are talking about the future. We are thinking about a particular condition or situation in the future, and the result of this condition. There is a real possibility that this condition will happen. For example, it is morning. You are at home. You plan to play tennis this afternoon. But there are some clouds in the sky. Imagine that it rains. What will you do?

if	condition	result
	Present Simple	will + base verb
If	it rains,	I will stay at home.

Notice that we are thinking about a future condition. It is not raining yet. But the sky is cloudy and you think that it could rain. We use the Present Simple tense to talk about the possible future condition. We use will + base verb to talk about the possible future result. The important thing about the first conditional is that there is a real possibility that the condition will happen.

Here are some more examples (do you remember the two basic structures: [if condition result] and [result if condition]?):

if	condition	result
	Present Simple	will + base verb
If	I see Mary,	I will tell her.
If	Tara is free tomorrow,	he will invite her.
If	they do not pass their exam,	their teacher will be sad.
If	it rains tomorrow,	will you stay at home?
If	it rains tomorrow,	what will you do?

result	if	condition
will + base verb		Present Simple
I will tell Mary	if	I see her.
He will invite Tara	if	she is free tomorrow.
Their teacher will be sad	if	they do not pass their exam.
Will you stay at home	if	it rains tomorrow?
What will you do	if	it rains tomorrow?

 

               Future Real Conditional

FORM

[If / When ... Simple Present ..., ... Simple Future ...]
[... Simple Future ... if / when ... Simple Present ...]
Notice that there is no future in the if- or when-clause.

USE

The Future Real Conditional describes what you think you will do in a specific situation in the future. It is different from other Real Conditional forms because, unlike the present or the past, you do not know what will happen in the future. Although this form is called "real", you are usually imagining or guessing about the future. It is called "real" because it is still possible that the action might occur in the future. Carefully study the following examples and compare them to the Future Unreal Conditional examples further down the page.

Examples:

• If I go to my friend's house for dinner tonight, I will take a bottle of wine or some flowers. I am still not sure if I will go to his house or not.
• When I have a day off from work, I am going to go to the beach. I have to wait until I have a day off.
• If the weather is nice, she is going to walk to work. It depends on the weather.
• Jerry will help me with my homework when he has time. I have to wait until he has time.
• I am going to read if there is nothing on TV. It depends on the TV schedule.
• A: What are you going to do if it rains?
  B: I am going to stay at home.

IMPORTANT If / When

Both "if" and "when" are used in the Future Real Conditional, but the use is different from other Real Conditional forms. In the Future Real Conditional, "if" suggests that you do not know if something will happen or not. "When" suggests that something will definitely happen at some point; we are simply waiting for it to occur. Notice also that the Simple Future is not used in if- clause or when- clause.

Examples:

• When you call me, I will give you the address. You are going to call me later, and at that time, I will give you the address.
• If you call me, I will give you the address. If you want the address, you can call me.

Future Unreal Conditional

FORM 1 (Most Common Form)

[If ... Simple Past ..., ... would + verb ...]
[... would + verb ... if ... Simple Past ...]

Notice that this form looks the same as Present unreal Condition

USE

The Future Unreal Conditional is used to talk about imaginary situations in the future. It is not as common as the Future Real Conditional because English speakers often leave open the possibility that anything MIGHT happen in the future. It is only used when a speaker needs to emphasize that something is impossible. Because this form looks like Present Unreal Conditional, many native speakers prefer Form 2 described below.

Examples:

• If I had a day off from work next week, I would go to the beach. I don't have a day off from work.
• I am busy next week. If I had time, I would come to your party. I can't come.
• Jerry would help me with my homework tomorrow if he didn't have to work. He does have to work tomorrow.

FORM 2

[If ... were + present participle ..., ... would be + present participle ...]
[... would be + present participle ... if ... were + present participle ...]

USE

Form 2 of the Future Unreal Conditional is also used to talk about imaginary situations in the future. Native speakers often prefer this form over Form 1 to emphasize that the conditional form is in the future rather than the present. Also notice in the examples below that this form can be used in the if-clause, the result, or both parts of the sentence.

Examples:

• If I were going to Fiji next week, I would be taking my scuba diving gear with me. In if-clause and result I am not going to go to Fiji and I am not going to take my scuba gear with me.
• If I were not visiting my grandmother tomorrow, I would help you study. In if-clause I am going to visit my grandmother tomorrow.
• I am busy next week. If I had time, I would be coming to your party. In result I am not going to come to your party.

FORM 3

[If ... were going to + verb ..., ... would be + present participle ...]
[... would be + present participle ... if ... were going to + verb ...]

USE

Form 3 of the Future Unreal Conditional is a variation of Form 2 which is also used to talk about imaginary situations in the future. Notice that this form is only different from Form 2 in the if-clause. Native speakers use Form 3 to emphasize that the conditional form is a plan or prediction in the same way " be going to" is used to indicate a plan or prediction.

Examples:

• If I were going to go to Fiji next week, I would be taking my scuba diving gear with me. I am not going to go to Fiji and I am not going to take my scuba gear with me.
• If I were not going to visit my grandmother tomorrow, I would help you study. I am going to visit my grandmother tomorrow.

IMPORTANT Only use "If"

Only the word "if" is used with the Past Unreal Conditional because you are discussing imaginary situations. "When" cannot be used.

Examples:

• I would buy that computer tomorrow when it were cheaper. Not Correct
• I would buy that computer tomorrow if it were cheaper. Correct

EXCEPTION Conditional with Modal Verbs

There are some special conditional forms for modal verbs in English:
would + can = could
would + shall = should
would + may = might
The words "can," "shall" and "may" cannot be used with "would." Instead, they must be used in these special forms.

Examples:

• If I went to Egypt next year, I would can learn Arabic. Unfortunately, that's not possible. Not Correct
• If I went to Egypt next year, I could learn Arabic. Unfortunately, that's not possible. Correct

The words "could," should," "might" and "ought to" include conditional, so you cannot combine them with "would."

Examples:

• If I didn't have to work tonight, I would could go to the fitness center. Not Correct
• If I didn't have to work tonight, I could go to the fitness center. Correct

Future Real Conditional vs. Future Unreal Conditional

To help you understand the difference between the Future Real Conditional and the Future Unreal Conditional, compare the examples below:

Examples:

• If you help me move tomorrow, I will buy you dinner. Future Real Conditional I don't know if you can help me.
• If you helped me move tomorrow, I would buy you dinner. Future Unreal Conditional You can't help me, or you don't want to help me.

 EXAMPLES:

 

• If it rains today, I'll stay at home.
  
• If he is busy now, I will come back tomorrow.
  
• If I have time, I'll visit my parents this afternoon.
  
• If it is warm tomorrow, we'll go to the beach.
  
• If it is cold, you must wear warm clothes.
  
• If he doesn't do his homework, he can not go to the party.
  
• If she doesn't call you, you can call her.
  
• If you work hard, you may become a millonaire someday.
  
• If you spend more than you earn, you'll become a poor man.
  
• If they don't invite you, you must not go.
  
• If we don't hurry, we'll miss our bus.
  
• If you pay now, you'll get a discount.
  
• If they don't want to go out, they can stay home.
  
• If you drink too much, you'll get drunk.
  
• If you feel sick, you must stay in bed.
  
• If they don't come here, we'll have to go there.
  

                          

                              

 

Present Unreal Conditional

FORM

[If ... Simple Past ..., ... would + verb ...]
[... would + verb ... if ... Simple Past ...]

USE

The Present Unreal Conditional is used to talk about what you would generally do in imaginary situations.

Examples:

• If I owned a car, I would drive to work. But I don't own a car.
• She would travel around the world if she had more money. But she doesn't have much money.
• I would read more if I didn't watch so much TV.
• Mary would move to Japan if she spoke Japanese.
• If they worked harder, they would earn more money.
• A: What would you do if you won the lottery?
  B: I would buy a house.
• A: Where would you live if you moved to the U.S.?
  B: I would live in Seattle.

EXCEPTION If I were ...

In the Present Unreal Conditional, the form "was" is not considered grammatically correct. In written English or in testing situations, you should always use "were." However, in everyday conversation, "was" is often used.

Examples:

• If he were French, he would live in Paris.
• If she were rich, she would buy a yacht.
• I would play basketball if I were taller.
• I would buy that computer if it were cheaper.
• I would buy that computer if it was cheaper. Not Correct (But often said in conversation.)

IMPORTANT Only use "If"

Only the word "if" is used with the Present Unreal Conditional because you are discussing imaginary situations. "When" cannot be used.

Examples:

• I would buy that computer when it were cheaper. Not Correct
• I would buy that computer if it were cheaper. Correct

EXCEPTION Conditional with Modal Verbs

There are some special conditional forms for modal verbs in English:
would + can = could
would + shall = should
would + may = might
The words "can," "shall" and "may" cannot be used with "would." Instead, they must be used in these special forms.

Examples:

• If I went to Egypt, I would can learn Arabic. Not Correct
• If I went to Egypt, I could learn Arabic. Correct

• If she had time, she would may go to the party. Not Correct
• If she had time, she might go to the party. Correct

The words "could," should," "might" and "ought to" include conditional, so you cannot combine them with "would."

Examples:

• If I had more time, I would could exercise after work. Not Correct
• If I had more time, I could exercise after work. Correct

• If he invited you, you really would should go. Not Correct
• If he invited you, you really should go. Correct

                                                

                      

 

Past Unreal Conditional

FORM

[If ... Past Perfect ..., ... would have + past participle ... ]
[... would have + past participle ... if ... Past Perfect ...]

USE

The Past Unreal Conditional is used to talk about imaginary situations in the past. You can describe what you would have done differently or how something could have happened differently if circumstances had been different.

Examples:

• If I had owned a car, I would have driven to work. But I didn't own one, so I took the bus.
• She would have traveled around the world if she had had more money. But she didn't have much money, so she never traveled.
• I would have read more as a child if I hadn't watched so much TV. Unfortunately, I did watch a lot of TV, so I never read for entertainment.
• Mary would have gotten the job and moved to Japan if she had studied Japanese in school instead of French.
• If Jack had worked harder, he would have earned more money. Unfortunately, he was lazy and he didn't earn much.
• A: What would you have done if you had won the lottery last week?
  B: I would have bought a house.
• A: What city would you have chosen if you had decided to move to the United States?
  B: I would have chosen Seattle.

IMPORTANT Only use "If"

Only the word "if" is used with the Past Unreal Conditional because you are discussing imaginary situations. "When" cannot be used.

Examples:

• I would have bought that computer when it had been cheaper. Not Correct
• I would have bought that computer if it had been cheaper. Correct

EXCEPTION Conditional with Modal Verbs

There are some special conditional forms for modal verbs in English:
would have + can = could have
would have + shall = should have
would have + may = might have
The words "can," "shall" and "may" cannot be used with "would have." Instead, they must be used in these special forms.

Examples:

• If I had gone to Egypt, I could have learned Arabic.
• If she had had time, she might have gone to the party.

The words "could," should," "might" and "ought to" include Conditional, so you cannot combine them with "would have."

Examples:

• If I had had more time, I could have exercised after work.
• If he had invited you, you might have gone.

for no possibility

If I had won the lottery, I would have bought a car.

The first conditional and second conditionals talk about the future. With the third conditional we talk about the past. We talk about a condition in the past that did not happen. That is why there is no possibility for this condition. The third conditional is also like a dream, but with no possibility of the dream coming true.

Last week you bought a lottery ticket. But you did not win. :-(

if	condition	result
	Past Perfect	would have + past participle
If	I had won the lottery,	I would have bought a car.

Notice that we are thinking about an impossible past condition. You did not win the lottery. So the condition was not true, and that particular condition can never be true because it is finished. We use the Past Perfect tense to talk about the impossible past condition. We use would have + past participle to talk about the impossible past result. The important thing about the third conditional is that both the condition and result are impossible now.

Look at these example senteces:

if	condition	result
	Past Perfect	would have + past participle
If	I had seen Mary,	I would have told her.
If	Tara had been free yesterday,	I would have invited her.
If	they had not passed their exam,	their teacher would have been sad.
If	it had rained yesterday,	would you have stayed at home?
If	it had rained yesterday,	what would you have done?

result	if	condition
would have + past participle		Past Perfect
I would have told Mary	if	I had seen her.
I would have invited Tara	if	she had been free yesterday.
Their teacher would have been sad	if	they had not passed their exam.
Would you have stayed at home	if	it had rained yesterday?
What would you have done	if	it had rained yesterday?