We have different ways of talking about the future. We often use going to (+ infinitive), the present continuous (to be + -ing) or will (+ infinitive). The structure we use depends on the function of what we want to say, whether we are talking about arrangements, plans, predictions, etc.
I thought will was the future tense in English.
It’s one of the ways of talking about the future, but there are a few others. Let’s look at will to start with. We use will / won’t (= will not) + the infinitive for predictions about the future.
Oliver’ll be back soon.
We won’t be ready.
Do you think it’ll rain this afternoon?
We also use will when we decide something at the moment of speaking.
(The doorbell rings) I’ll get it.
So, you sometimes use the verb think before will?
Yes, that’s very common. We also use: don’t think, expect, be + sure.
I’m sure you’ll have a good time.
You said will is used for decisions made at the moment of speaking. What about decisions made before the moment of speaking?
Then we can use either the present continuous or going to (+ infinitive).
Amy’s coming round.
We’re going to watch a film – want to join us?
What are you doing this evening?
Is there a difference between them?
We use the present continuous more for arrangements with other people and be + going to + infinitive for intentions. Sometimes it’s important to choose the right structure, but often we could use either because many events are both arrangements and intentions.
Amy’s coming round. (= arrangement between Amy and Daisy)
Amy’s going to come round. (= Amy’s intention)
I’m going to clean my room tonight. (= intention)
I’m cleaning my room tonight. (not an arrangement)
So could I say 'I’m going to go to the cinema with Alex'?
Yes, that’s correct. But we usually avoid saying going to go, just because it doesn’t sound very elegant. We normally use the present continuous with go.
I’m going to the cinema with Alex.
And 'I will go to the cinema with Alex'?
No. We don’t use will for arrangements or intentions if the decision was made before the moment of speaking.
Oh, yes, you told me that before. Anything else?
Yes, there’s another use of going to. We use it for predictions too, especially when you can see something happening or about to happen.
Look out! You’re going to spill that coffee.
Can you use going to for other predictions?
Yes, sometimes both will and going to can be used.
I think the Green Party will win the election.
I think the Green Party are going to win the election.
OK, and one last thing! Is it correct to say, ‘When’s the race?’ That’s present simple, isn’t it?
Yes. You can use present simple for timetabled events.
My plane leaves at 4pm tomorrow.
The match starts at 8pm.
Phew! So sometimes you can use going to or the present continuous and sometimes you can use will or going to. And you can also use present simple for timetabled events. I’ll never understand the future!
I’m sure you will! You’re using it correctly already.