Unit 16: Real Possibilities — If, When and Unless

What will happen?

We often talk about the future by imagining a situation and saying what will happen as a result.

If it rains tomorrow, we'll stay at home.
If the weather is fine, we'll go for a walk.

In this unit, you will practise making these sentences, asking questions, and talking about your own plans.

Step 1

Real possibilities

Read the sentences. Imagine each situation. What will happen next?

If it rains tomorrow, we'll stay at home.
If it doesn't rain, we'll go for a walk.
The weather is not certain. We imagine two possible outcomes.

If I miss the bus, I'll be late.
If she works hard, she'll get a pay rise.
If they leave now, they'll arrive on time.

Choose a possible result

Complete each sentence by choosing the most natural ending.

1. If I don't set my alarm, …

2. If we save enough money, …

3. If you eat too much, …

Step 2

The basic pattern

If + present simple, will + base form

Look at the two parts of each sentence:

If she works hard,
present simple

she will get a pay rise.
will + base form

We can put the result first, too: She will get a pay rise if she works hard. We do not usually need a comma when the sentence begins with the result.

In this pattern, use the present simple after if, not will:
✓ If he comes, I'll talk to him.
✗ If he will come, I'll talk to him.

Complete the sentences

Use the verb in brackets. Write the correct form in each gap.

1. If Nadia ______ (finish) work early, she will call us.

2. If you study tonight, you ______ (feel) more confident tomorrow.

3. We will miss the train if we ______ (not / leave) soon.

4. If Leo ______ (not / hurry), he'll be late.

Remember: after will, use the base form: will feel, not will feels.

Step 3

Will, may and might

We do not always know what will happen. We can show how certain we feel.

Example	Meaning
If the weather is good, we'll go for a walk.	This is our plan.
If the weather is good, we may go for a walk.	It is possible.
If the weather is good, we might go for a walk.	It is possible; we are not sure.

May and might are followed by the base form, just like will.

Choose the best form

1. If I finish my work early, I ______ come and see you. (It is possible, but I am not sure.)

2. If the train is on time, we ______ arrive before six. (This is our expected plan.)

Speak together

Finish these sentences with your own ideas. Compare answers with a partner.

If I have some free time this evening, I might …
If the weather is good this weekend, I'll …
If I feel tired tomorrow, I may …

Step 4

If and when

Compare these sentences:

If I see Maria, I'll tell her.
I don't know whether I'll see her.

When I see Maria, I'll tell her.
I expect to see her.

If leaves the situation open. When often suggests that the speaker expects it to happen. Both can refer to the future.

In future time clauses with if and when, we normally use the present simple, not will:
✓ When I get home, I'll phone you.
✗ When I will get home, I'll phone you.

Choose if or when

Choose the word that best fits the meaning in brackets.

1. ______ I get home tonight, I'll make some dinner. (I expect to get home.)

2. ______ I see a ghost, I'll take a photograph! (This is unlikely.)

3. I'll let you know ______ I hear any news. (I am waiting for news and expect to hear.)

In real conversation, both if and when can sometimes be possible. Here, choose the word that best matches the meaning in brackets.

Step 5

Unless

Unless often means if … not.

Unless you hurry, you'll miss the train.

If you don't hurry, you'll miss the train.

The two sentences have the same basic meaning. Notice that we do not normally add another negative after unless in this pattern.

✓ Unless it rains, we'll have the picnic.
✓ If it doesn't rain, we'll have the picnic.
The meaning is “if it does not rain”.

Rewrite using unless

Keep the meaning. Use the verb in brackets where it is supplied.

1. If you don't leave now, you'll miss the bus. → ______ you leave now, you'll miss the bus.

2. If she doesn't practise, she won't improve. → She won't improve ______ she practises.

3. If we don't book a table, we may not get one. → ______ we book a table, we may not get one.

Make your own sentences

Unless I get up early, …
Unless I have a lot of work to do, …
Unless the weather is terrible, …

Step 6

A story: Plans for Saturday

Read the story. Notice how the characters talk about possible plans and what they will do if things change.

On Friday evening, Nadia phoned her friend Leo.

“If the weather is fine tomorrow, shall we go cycling?” she asked.

“That sounds good,” Leo said. “If I finish my jobs in the morning, I'll meet you at ten. If I don't finish, I might be a little late.”

“All right. I'll wait for fifteen minutes. Unless it rains, we'll go to the park. When we get there, we can decide where to ride.”

On Saturday morning, the sky was grey. Nadia sent Leo a message: “If it rains, I'll take the bus to the museum instead. Let me know what you decide.”

Leo replied, “I've finished my jobs, and it isn't raining here. I'll meet you at ten. If the weather gets worse, we'll go to the museum together.”

At ten o'clock, they met outside the station. The rain had stopped, so they went cycling after all.

Check your understanding

1. What will Leo do if he finishes his jobs in the morning?

2. What does Nadia mean by “Unless it rains”?

3. What will they do if the weather gets worse?

Find examples in the story

Find and copy one sentence containing each of these words: if, when, unless. Then explain the situation in your own words.

Pairwork: What will you do?

Student A asks the questions. Student B answers with a real idea. Ask a follow-up question when you can.

What will you do if it rains this weekend?
What will you do when you get home today?
What will you do unless you have too much work?
If you have a free day next week, where might you go?
What will you do if your bus or train is late?

Write about your plans

Write five or six sentences about the next few days. Use if at least twice, when once and unless once. Include the base verbs in your first draft if they help you plan the sentences.

Remember

If + present simple, will/may/might + base form: If I have time, I'll call you.
When + present simple can refer to an expected future event: When I arrive, I'll text you.
Unless often means if … not: Unless you hurry, you'll be late.
In these future condition and time clauses, we normally use the present simple after if and when, not will.

Teaching notes

Use familiar real-life situations and invite learners to supply their own outcomes. Mime or draw a situation if needed before asking learners to complete the sentence. The written exercises reinforce the teacher's presentation; they are not intended to replace it.

Encourage learners to read their sentences aloud and compare different plausible answers. The multiple-choice exercises guide learners towards the intended meaning, but in open speaking and writing tasks, more than one answer may be correct.