Using Conditional Sentences in English - 5 Levels of Difficulty

Hi, I’m Stephanie.

Welcome to Oxford Online English!

In this lesson, you can learn about conditional sentences.

Conditional sentences are sentences with the word ‘if’.

You can use conditional sentences to talk about many different situations.

There are also sentences which don’t use the word ‘if’, but which follow similar

rules.

By the way, do you want English subtitles while watching this video?

Click the ‘CC’ button in the bottom right now to turn on English subtitles if you need

them.

This is a ‘5 levels’ lesson.

That means you’ll see five sections.

Each section will give you a challenge.

Each section is more difficult than the previous one.

If you’re a more advanced English speaker, you should probably skip to level two.

Ready?

Let’s go!

Look at the five sentences.

Your job is to put the verb in brackets into the correct form.

Pause the video and do it now.

Ready?

Here are the answers.

So, what do you need to know here?

These sentences are called first conditionals.

They talk about things which could happen in the future.

All conditional sentences have two parts.

They have an if-clause… …and a *result* clause.

You need to know three basic things to make first conditional sentences.

One: after ‘if’, use a present tense.

Here, you use the present simple.

Other present tenses are sometimes possible, but you can almost always use the present

simple.

Even though you’re talking about the future, you generally can’t use a future form after

‘if’; you use a present verb tense to talk about the future.

Two: in the result clause – meaning the other part of the sentence – use a future

form.

You can use different future forms, like ‘will’, ‘going to’, or the present continuous.

Three: you can change the order of the clauses; you can put the if-clause at the start of

the sentence, or you can start with the result clause, and the if-clause goes afterwards.

With these three points, you can make first conditional sentences to talk about things

which might happen in the future.

However, there are many other kinds of conditional sentence.

Let’s move on to level two!

Look at your sentences for level two.

Here, you have a different task.

Some of these sentences are correct, but some are not.

Your job is to find the mistakes and correct them.

Pause the video and think about it.

Take as much time as you need!

Could you do it?

Let’s look together.

Sentences one and two are correct.

These are called zero conditionals.

A zero conditional uses the present simple in both parts of the sentence.

Use zero conditionals to talk about things which are generally true.

Sentence three is incorrect, but four is correct.

Can you explain why?

‘Unless’ means ‘if not’.

You can’t use a negative verb after ‘unless’, because you can’t have two negatives together

in English.

So, sentence three should be ‘Unless you *have* further questions, let’s move on

to the next point.’

Finally, sentence five is also incorrect.

There are many words which behave similarly to ‘if’.

‘Until’ is one such word; others include ‘as soon as’, ‘when’, ‘in case’

and ‘unless’.

Like with ‘if’, you can’t generally use a future form after these words.

Instead, you use a present verb – usually the present simple – to refer to the future.

So, sentence five should be ‘I can’t do any work until my computer *is* fixed.’

Did you get everything right?

If so, great!

If not, don’t worry.

Remember that you can always review a section if you need to.

Here are your sentences.

This time, you have to put both verbs into the correct form.

Here’s a tip: not all the sentences follow the same pattern.

Think carefully!

For one verb, there are two possible answers.

Pause the video and make your answers now.

Done?

Take a look.

How did you do?

Did you get them all right?

If not, what do you need to study?

These sentences are all second and third conditionals.

Second and third conditionals are *unreal* conditionals.

That means you use them to talk about imaginary situations – situations that didn’t really

happen, or won’t happen.

For example, look at sentence two: ‘If I were president, I’d send everyone a cake

on their birthday.’

But, I’m not president, and I’m not going to be.

It’s an unreal, imaginary situation.

So, no cake for you!

You use second conditionals to talk about unreal situations in the present or future.

You use third conditionals to talk about unreal situations in the past.

Look at the five sentences again.

Which ones are second conditionals, and which are third conditionals?

One, two and four are second conditionals; they refer to the present or the future.

Three and five refer to the past, so they’re third conditionals.

If you find this difficult, start by reviewing second conditional sentences.

Also, study the difference between real and unreal conditionals.

Many languages don’t make a difference between real and unreal situations like English does.

If your language doesn’t do this, then you’ll need to pay extra attention to these unreal

sentences when you’re speaking English.

When you feel that you understand second conditionals well, then learn and practise third conditionals.

So, is that it?

Have we seen all the possible types of conditional sentences?

Not quite yet.

In level four, let’s do something a little different.

Look at the sentences to begin.

You have two jobs here.

One: are both verb forms possible, or not?

If not, which one is right?

Two: if both are possible, is there any difference in meaning?

If so, what?

Pause the video now.

You know what to do!

OK, before we look at the answers, here’s a clue: there’s only one sentence where

both verb forms are possible.

If that’s news to you, then feel free to pause again and take more time to think about

it.

Ready now?

Let’s check!

Like in level three, all these sentences are *unreal* conditionals.

They’re talking about things which didn’t happen or won’t happen in reality.

But, these are mixed conditionals.

That means the one part of the sentence is about the present or future, and the other

part is about the past.

For example, in sentence two, the first clause – which is the result clause – is about

the present, and the if-clause is about the past.

In sentence three, the result clause is about the future, and the if-clause is about the

past.

In sentence one, both forms are possible.

Sentence one can also be a third conditional, referring to the past.

However, it can also be a mixed conditional, with the if-clause referring to the present,

and the result clause referring to the past.

Here’s the question you probably want an answer to: what’s the difference between

using the two forms in sentence one?

Can you explain it?

If you use ‘wasn’t’, and say ‘if she wasn’t so shy’, then you’re referring

to the present.

This suggests that she’s generally shy – this is part of her personality.

If you say ‘if she hadn’t been so shy’, then you’re referring to the past.

This suggests that she was shy during her stay here, but maybe she’s not shy all the

time.

This is a small difference, but it is a difference nonetheless.

Another question: how do you know there’s only one possibility for sentences two to

five?

It’s because all these sentences contain a time marker.

For example, sentences two and four include the word ‘now’.

So, they must be about the present.

Sentences three and five contain time markers which clearly refer to the past.

So, what should you do if you found this difficult?

First, review second and third conditionals, and how to form them.

If you have difficulties with the formation of second or third conditional sentences,

then you’ll struggle with mixed conditionals, too.

Then, try to make some mixed conditional sentences about your life.

Think of things you did – or didn’t do – in the past, which could have made a difference

to your life now.

Or, think about your personality traits, and how your past might have been different if

you had a different personality.

If you want extra practise, add your examples in the comments!

OK, there’s one more section.

Are you ready for the toughest challenge?

Look at your level five sentences.

Your job is to complete each sentence with *one* word.

There’s only one answer that makes sense, except for number five, where there are at

least two possible answers.

Pause the video and find your answers.

Could you do it?

These sentences test some extremely specific grammar knowledge.

Let’s see the answers.

So, can you explain what’s happening here?

Some of these sentence might look strange or wrong, but they’re all correct.

By the way, in sentence five, ‘would’ is – we think – the most likely answer,

but ‘will’ and ‘could’ are also possible.

In sentence one, using the present perfect, instead of the present simple, means that

this person has already taken their English exam, but doesn’t know the results yet.

Usually in first conditional sentences, you might be able to use other present tenses,

but you can always use the present simple.

However, there’s one case where you *must* use the present perfect.

If you’re talking about the future consequences of something which happened in the past, you

need the present perfect after ‘if’.

In this case, the event – the exam – is in the past, but the consequences – meaning

the results – are in the future.

Sentence two is a more formal or literary style.

The more common pattern would be ‘if you had told us sooner…’

You can use this formal style if the first verb after ‘if’ is ‘had’, ‘should’

or ‘were’.

To form the sentence, you do two things.

One: you omit ‘if’.

Two: you move the auxiliary verb – ‘had’, ‘should’ or ‘were’ – before the

subject.

It’s never necessary to use this pattern; you can always use a regular conditional,

with ‘if’, instead.

What about sentence three?

In second conditional sentences, if the verb after ‘if’ describes an action, you can

add ‘were to’ before the verb.

This emphasises that the situation is very distant or unlikely.

When you use this, you’re saying ‘I really don’t think this will happen.’

In this case, the interviewer is probably not very positive about this candidate!

Again, you never need to use this structure.

You could make a regular second conditional: ‘if we decided to hire you…’

In sentence four, what do you think is happening?

You might be thinking: you can’t use ‘will’ after ‘if’ in a conditional sentence.

That’s generally true, but this sentence isn’t really a conditional.

‘If’ here does not express a condition; it is similar in meaning to ‘in case’.

You can understand the sentence as ‘You can take it, because it might help you.’

So, the regular rules about first conditionals don’t apply here, and you can – and should

– use ‘will’ after ‘if’.

Sentence five might also look weird to some of you.

Can you explain it?

Why is there only one part?

Don’t conditionals need to have two parts?

Like with number four, this isn’t a conditional.

It’s a formal way of making a request.

The meaning is equivalent to ‘Would you please follow me?’

Because it isn’t a conditional, it doesn’t need a result clause – you can just use

an if-clause by itself.

Remember that this is a formal style, and you’re not likely to hear it or use it often.

Now, we have one final question for you: what topic from this lesson would you like to learn

more about?

Please let us know in the comments!

Thanks for watching!

See you next time!