B1 · Intermediate Chapter 17

Expressing Degrees of Certainty

3 Total Rules
36 examples
5 min
Rules in This Chapter Quick Practice

Chapter in 30 Seconds

Move beyond simple 'will' to express advice, permission, and varying levels of possibility.

  • Replace 'will' with modals like 'should' to give conditional advice.
  • Use 'might' and 'may' to express uncertain future outcomes.
  • Apply 'can' to describe potential abilities or granted permissions.
Master the spectrum of certainty in your future plans.

What You'll Learn

Want to share how likely something is, or offer advice for the future? Dive into this chapter and discover how to use the First Conditional with words like 'maybe' and 'should' to express different certainties. You'll be predicting and advising with confidence!

Learning Objectives

By the end of this chapter, you will be able to:

  1. 1
    By the end you will be able to provide conditional advice using 'should' in the main clause.
  2. 2
    By the end you will be able to distinguish between certain and uncertain outcomes using 'might' and 'may'.
  3. 3
    By the end you will be able to offer permission or describe future abilities based on specific conditions.

Chapter Guide

Overview

Mastering how to talk about possibilities and give advice is a crucial step in sounding more natural and confident in English. At the B1 English grammar level, you're ready to move beyond simple predictions and start sharing how likely something truly is, or offering nuanced suggestions for the future. This chapter focuses on expressing degrees of certainty using the versatile First Conditional. Instead of always saying "will," we'll explore how words like 'can', 'might', and 'should' allow you to convey everything from a strong recommendation to a tentative guess. You’ll learn how to predict outcomes with different levels of confidence and give advice effectively, preparing you for a wider range of real-world conversations and making your English sound much more sophisticated and precise. Get ready to predict and advise like a pro!

How This Grammar Works

At its heart, the First Conditional structure is "If [condition], then [result]." Typically, we use "will" in the result clause (e.g., "If it rains, I will stay home."). However, to express different degrees of certainty or add more specific meanings like advice or ability, we can swap "will" for various modal verbs or probability adverbs.
When you want to express a *possible, but uncertain* future result, you can use 'may' or 'might' instead of 'will'. For example: "If I finish work early, I may go to the gym" or "If she calls, I might answer." Both 'may' and 'might' signal that the outcome isn't guaranteed – it's just a possibility. We can also use adverbs like 'maybe' or 'probably' with 'will' to achieve a similar effect of reduced certainty: "If I have time, I'll maybe visit you" or "If the weather is good, we'll probably go to the beach." These adverbs often sound a bit more casual.
Using 'can' in the result clause of a First Conditional sentence adds another layer of meaning. It can indicate a future possibility or ability that depends on the condition: "If you study hard, you can pass the exam" (ability). It can also convey permission: "If you finish your homework, you can watch TV" (permission). So, 'can' is perfect for when the condition enables an action.
Finally, swapping 'will' for 'should' transforms the result into a recommendation or advice. "If you feel unwell, you should see a doctor." Here, 'should' makes the result clause an advisable action rather than a simple prediction. By mastering these small changes, you can convey a much richer spectrum of meaning in your future predictions and advice.

Common Mistakes

Here are some common pitfalls when expressing degrees of certainty with the First Conditional:
  1. 1✗ If it will rain, I might stay home.
✓ If it rains, I might stay home.
*Explanation:* Remember, the 'if' clause in the First Conditional uses the present simple tense, not future. The modal verb (like 'might') goes in the result clause.
  1. 1✗ If I finish early, I probably will go.
✓ If I finish early, I will probably go. OR If I finish early, I 'll probably go.
*Explanation:* When using adverbs like 'probably' or 'maybe' with 'will', they usually come *between* 'will' and the main verb, or after the contraction 'll.
  1. 1✗ If you study, you can pass better.
✓ If you study, you can pass the exam.
*Explanation:* 'Can' expresses ability or permission; it doesn't modify the *quality* of passing. Ensure 'can' is used correctly for what is possible or allowed.

Real Conversations

A

A

If you don't hear from me by 6 PM, I might be stuck in traffic.
B

B

Okay, I'll call you then. If you can't make it, just send a quick text.
A

A

I'm not sure what to do about my presentation.
B

B

If you practice more, you should feel more confident. If you still struggle, maybe I can help you rehearse.
A

A

Do you think we'll finish this project on time?
B

B

If everyone cooperates, we can definitely get it done. But if we encounter any unexpected problems, we may need an extension.

Quick FAQ

Q

What's the difference between "If it rains, I will stay home" and "If it rains, I might stay home"?

"Will" implies you are certain about your action if the condition is met. "Might" suggests there's a possibility you'll stay home, but it's not guaranteed. You're expressing a lower degree of certainty with "might."

Q

Can I use "maybe" or "probably" with "might" or "may"?

While grammatically possible (e.g., "If it rains, I might maybe stay home"), it's often redundant and sounds less natural. Stick to one way of showing probability for clarity: either "will probably" or just "might/may."

Q

Is "can" in the First Conditional always about ability?

No, 'can' can also express permission ("If you finish your dinner, you can have dessert") or future possibility ("If the store is open, you can buy milk there"). The context usually makes the meaning clear.

Cultural Context

Native English speakers often use these variations to soften direct statements or appear less assertive, especially when giving advice or making predictions. For instance, "You should do this" is advice, but "If you have time, you could do this" is a gentler suggestion. In informal speech, you might hear "If I see him, I'll maybe tell him" which is very common. The choice of modal can subtly reflect politeness, confidence, or hesitancy, making communication more nuanced and natural.

Key Examples (6)

1

If you study hard, you `can` pass the exam easily.

First Conditional: Using Modals (can, might, should)
2

If it rains tomorrow, we `might` stay home and watch movies.

First Conditional: Using Modals (can, might, should)
3

If you don't hydrate enough, you `will probably` feel tired later.

First Conditional: Maybe/Probably (May/Might)
4

If the concert sells out quickly, we `may` not get tickets.

First Conditional: Maybe/Probably (May/Might)
5

If it rains, we can stay inside and play games.

First Conditional with 'Can' (Future Possibility & Permission)
6

You can borrow my book if you promise to return it.

First Conditional with 'Can' (Future Possibility & Permission)

Tips & Tricks (3)

💡

The Comma Rule

If the 'If' comes first, use a comma. If the 'If' is in the middle, no comma is needed. 'If I go, I can see.' vs 'I can see if I go.'
frontend.learn_grammar.from_rule: First Conditional: Using Modals (can, might, should)
💡

Interchangeability

In 99% of cases, you can use 'may' and 'might' interchangeably. Don't stress about the difference!
frontend.learn_grammar.from_rule: First Conditional: Maybe/Probably (May/Might)
⚠️

The 'Will' Trap

Never say 'If I will can'. It's the most common mistake. Just say 'If I can' or 'If I [verb], I can'.
frontend.learn_grammar.from_rule: First Conditional with 'Can' (Future Possibility & Permission)

Key Vocabulary (6)

probability the extent to which something is likely to happen outcome the result or consequence of an action permission the act of allowing someone to do something advice guidance or recommendations offered with regard to prudent future action certainty the state of being completely confident or sure of something condition something that must happen or be true before something else can happen

Real-World Preview

map

A Weekend Trip Plan

Review Summary

  • If + Present Simple, [Subject] + should/might/can + Verb

Common Mistakes

You cannot use 'will' and 'might' together. 'Might' already implies a future possibility.

Wrong: If it rains, I will might stay home.
Correct: If it rains, I might stay home.

Modal verbs like 'should' replace 'will' entirely in the result clause of a conditional.

Wrong: If you are tired, you will should rest.
Correct: If you are tired, you should rest.

In English, 'will can' is ungrammatical. Use 'can' for the conditional result or 'will be able to'.

Wrong: If I study hard, I will can speak English.
Correct: If I study hard, I can speak English (or 'I will be able to speak').

Next Steps

You're making incredible progress! By mastering these nuances, you're sounding much more like a fluent English speaker. Keep it up!

Write 3 'If' sentences giving advice to a tourist in your city.

Record yourself explaining three things you might do if you win the lottery.

Continue to: Getting Started with the Present Perfect

Quick Practice (10)

Choose the best modal for advice.

If you feel tired, you ___ take a nap.

✓ Correct! ✗ Not quite. Correct answer: a
'Should' is the best choice for giving advice.

frontend.learn_grammar.from_rule: First Conditional: Using Modals (can, might, should)

Fill in the correct form of the verb in the 'if' clause.

If he ___ (study) more, he might pass the test.

✓ Correct! ✗ Not quite. Correct answer: studies
The 'if' clause in a first conditional uses the Present Simple.

frontend.learn_grammar.from_rule: First Conditional: Maybe/Probably (May/Might)

Fill in the blanks with the correct form of the verbs.

If she ___ (have) enough money, she ___ (can/buy) the car.

✓ Correct! ✗ Not quite. Correct answer: has / can buy
We use Present Simple after 'if' and 'can' + base verb for the result.

frontend.learn_grammar.from_rule: First Conditional with 'Can' (Future Possibility & Permission)

Find the mistake in the sentence.

Find and fix the mistake:

If you will study hard, you might pass the exam.

✓ Correct! ✗ Not quite. Correct answer: a
You cannot use 'will' in the if-clause of a first conditional.

frontend.learn_grammar.from_rule: First Conditional: Using Modals (can, might, should)

Fill in the correct form of the verb and the modal.

If it ___ (be) sunny tomorrow, we ___ (can / go) to the park.

✓ Correct! ✗ Not quite. Correct answer: a
We use the present simple 'is' in the if-clause and 'can go' in the result clause.

frontend.learn_grammar.from_rule: First Conditional: Using Modals (can, might, should)

Choose the correct modal for an uncertain result.

If we leave now, we ___ catch the early bus, but I'm not sure.

✓ Correct! ✗ Not quite. Correct answer: might
Because the speaker is 'not sure', 'might' is the correct choice.

frontend.learn_grammar.from_rule: First Conditional: Maybe/Probably (May/Might)

Select the best response.

Can I borrow your bike?

✓ Correct! ✗ Not quite. Correct answer: Yes, if you are careful, you can.
Standard first conditional with permission.

frontend.learn_grammar.from_rule: First Conditional with 'Can' (Future Possibility & Permission)

Which sentence is formal?

Choose the formal version.

✓ Correct! ✗ Not quite. Correct answer: a
'Require', 'assistance', and 'may' are formal markers.

frontend.learn_grammar.from_rule: First Conditional: Using Modals (can, might, should)

Find the mistake in the sentence.

Find and fix the mistake:

If you can to help me, I can finish early.

✓ Correct! ✗ Not quite. Correct answer: If you help me
While 'If you can help' is possible, 'can to' is always wrong. The simplest form is 'If you help me'.

frontend.learn_grammar.from_rule: First Conditional with 'Can' (Future Possibility & Permission)

Which sentence is grammatically correct?

Choose the correct sentence:

✓ Correct! ✗ Not quite. Correct answer: If it rains, we can't play.
No 'will' after 'if' and no 'will' before 'can't'.

frontend.learn_grammar.from_rule: First Conditional with 'Can' (Future Possibility & Permission)

Score: /10

Common Questions (6)

Yes, you can use could to show a theoretical ability or a very polite suggestion, though it's more common in the second conditional. In the first conditional, it means 'it is possible that we will be able to'.
In English, the if-clause sets the condition, and we use the present tense to represent that condition as a fact or a real possibility. Using will there is redundant and grammatically incorrect in standard English.
In modern English, there is almost no difference. Might is more common in speech, while may is slightly more formal. Some grammarians say might is even less certain than may, but most people use them the same way.
Yes! Could also expresses possibility. 'If it rains, we could stay home' means it is a possible option for us.
Yes, but it changes the meaning. Can is for real/likely situations (First Conditional). Could is for imaginary/unlikely situations (Second Conditional).
Usually 'If I'. For example: 'If I go, I can buy it.' If you say 'If I can go', you are saying 'If I have the ability to go'.
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Refining Your Future Conditions
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Getting Started with the Present Perfect
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