What Are Future Time Clauses and Conditionals?

Future time clauses and conditionals are sentence structures that connect two events or actions in the future. One part of the sentence describes a condition or a point in time, and the other part describes what will happen as a result.

They are essential for talking about:

• Future plans and arrangements.
• Possible future situations and their consequences.
• Giving advice or instructions for future actions.

How Do We Form Future Time Clauses?

The main rule for future time clauses and conditionals is simple: use a present simple verb in the clause that introduces the condition or time, even when you are talking about the future.

The other part of the sentence, the main clause, will use a future form or an imperative:

• will + base verb: If it rains, I will stay home.
• be going to + base verb: When she arrives, we are going to start dinner.
• Imperative: As soon as you finish, call me.

You can put the time clause at the beginning or at the end of the sentence. If it comes first, use a comma after it.

Common Connectors for Future Time Clauses

Many different words and phrases can introduce future time clauses:

• If: Used for a possible condition. If I have time tomorrow, I'll visit you.
• When: Used for a certain event in the future. When I finish work, I'll go to the gym. (This implies I will finish work.)
• As soon as: Means "immediately after." As soon as the bell rings, the students will leave.
• Unless: Means "if not." Unless it stops raining, we won't go out. (This means If it doesn't stop raining...)
• As long as: Means "only if" or "provided that." You can borrow my car as long as you fill it with petrol.
• Provided (that): Similar to as long as, it sets a condition. Provided you study hard, you will pass the exam.
• In case: Used to talk about precautions for a possible future situation. Take an umbrella in case it rains. (Not if it rains, but to be prepared for the possibility.)

Present Simple vs. Present Perfect in Time Clauses

Sometimes, you can use either the present simple or the present perfect in future time clauses, especially with when and as soon as.

• Using the present simple focuses on the action itself: I'll call you when I arrive.
• Using the present perfect emphasizes the completion of the action before the next one starts: I'll call you when I have arrived.

Often, there is very little difference in meaning, but the present perfect can sound slightly more formal or emphasize the completion.

The Special Case of 'If' (Meaning 'Whether')

Be careful when if means whether. In this situation, if is not introducing a condition, but rather an indirect question or uncertainty.

When if means whether, you can use will or be going to after it, because it's not a conditional clause.

• Correct: I don't know if I will go to the party. (Here, if means whether.)
• Incorrect (for a condition): I don't know if it rains tomorrow. (This would mean I don't know the condition of rain tomorrow, which is not the intended meaning.)

If you are talking about a condition, always use the present simple after if.

Examples

• If you study regularly, you will improve your English quickly.
• When the sun sets, we are going to light a bonfire.
• As soon as I receive the email, I'll forward it to you.
• Unless you apologize, she won't speak to you.
• You can use my laptop as long as you are careful with it.
• Provided that the weather is good, we'll have a picnic.
• I'll take my phone in case I need to call for help.

Practice

Common mistakes for Spanish speakers

A very common mistake for Spanish speakers is to use a future tense verb in the time clause. In Spanish, you often use the future subjunctive or future indicative in these clauses (e.g., cuando llueva, si lloverá).

However, in English, you must use a present simple verb:

• Incorrect: If it will rain tomorrow, I will stay home.
• Correct: If it rains tomorrow, I will stay home.
• Incorrect: When I will finish my homework, I will watch TV.
• Correct: When I finish my homework, I will watch TV.

Remember: no will or be going to in the clause that starts with if, when, as soon as, etc. (unless if means whether).

Frequently asked questions

Why do we use the present simple for future events in these clauses?

We use the present simple because the time clause sets a condition or a point in time that must happen before the main future action. It's a grammatical rule, not a logical one about time.

What's the difference between 'if' and 'when'?

If introduces a condition that may or may not happen: If it snows, we'll go skiing. When introduces an event that is certain to happen: When it snows this winter, we'll go skiing.

Can I use 'will' after 'in case'?

No, just like other time clauses, you use the present simple after in case. For example: Take a jacket in case it gets cold. (Not in case it will get cold).

Is this grammar point important for B2 exams?

Yes, understanding future time clauses and conditionals is crucial for B2 exams like Cambridge FCE or IELTS. You'll need to use them accurately in writing tasks (e.g., essays, reports) and speaking parts to express complex ideas about future plans, predictions, and hypothetical situations.

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