1. Prediction: what you think will happen
A prediction is an expectation about a future event or state. The speaker does not necessarily control it: they predict the weather, a result, a delay, or another person's reaction.
Do not confuse a prediction with a plan. In a statement about rain, nobody is planning the rain; in a statement about repairing one's own home, the speaker may be reporting a decision that has already been made. Here we are practising predictions, not the timing of decisions.
The room is going to be cold tonight.
The room is going to be cold tonight.
The speaker predicts the room's state, not a plan for it.
I think you will enjoy the course.
I think you will enjoy the course.
This is the listener's expected reaction. The speaker is not promising to make them like the course.
2. Going to: focusing on signs now
Am/is/are going to + verb often shows: “Look at the situation now—this is what seems likely to happen next.” The basis may be what we see, hear, or already know about the current situation.
A sign and a prediction are not the same thing. The box near the edge has not fallen yet. A prediction with going to does not turn a future event into an established fact.
The box is moving towards the edge. It's going to fall.
The box is moving towards the edge. It's going to fall.
The box's movement is the present sign; falling is the prediction.
The battery is almost empty. My phone is going to switch off soon.
The battery is almost empty. My phone is going to switch off soon.
The speaker connects the prediction with the current charge. They do not invent a cause for the malfunction.
3. Will: expressing an expectation or opinion
Will + verb is a common way to make a prediction: what you think will happen or what the situation will be like. I think helps state the opinion directly, but it is not required.
A prediction with will can also be based on knowledge or data. For example, a weather presenter may use measurements and still say will. Having evidence does not make this form incorrect.
I think the new café will be popular.
I think the new café will be popular.
The speaker gives their assessment of the café's future success.
It will be warm tomorrow.
It will be warm tomorrow.
This is a usual way to phrase a prediction, including a prediction based on weather data.
4. Both forms can be appropriate
The difference is not simply “opinions use only will, and signs use only going to.” You can say I think it's going to rain. In the warning Careful! You'll fall!, will is also possible.
Do not choose the form only because of words such as tomorrow, soon, or I think. There is no universal percentage scale of certainty and no rule that “going to means the near future, while will means the distant future.” The whole context and what the speaker wants to focus on are important.
If an exercise explicitly asks you to use going to, a sentence with will may be grammatical but may not meet the learning requirement. When no form is specified and both sound natural, both are acceptable.
I think the lesson will be interesting. / I think the lesson is going to be interesting.
I think the lesson will be interesting. / I think the lesson is going to be interesting.
Both predictions are possible. I think alone does not determine the form.
Careful! Your bag will break! / Careful! Your bag is going to break!
Careful! Your bag will break! / Careful! Your bag is going to break!
Both statements can warn about danger. Going to connects the prediction more clearly with what is already happening to the bag.
5. Affirmative statements: two constructions
After will, use the base form of the verb without to: will rain, will work, will be. Do not add the -s ending after will, even with he, she, or it.
Before going to, use am, is, or are according to the subject: I am; he/she/it is; you/we/they are. The base form also follows going to: going to rain, going to be.
Contractions are possible in ordinary statements: I'll, you'll, she'll, we'll, they'll; I'm, it's, we're. They do not change the meaning of the prediction.
Subject + will + base form of the verb. / Subject + am/is/are going to + base form of the verb.
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
- V1 / base form —
- The base verb without to: work, go, be.
She will like the room. / She'll like the room.
She will like the room. / She'll like the room.
Like has no -s; she'll means she will.
The roads are going to be busy.
The roads are going to be busy.
Roads is plural, so use are; after going to, be is needed, not are.
6. Negative predictions
Will not or won't makes a prediction negative. In the going to construction, put not after am/is/are: is not going to, aren't going to. Don't is not needed before will.
Keep the exact scope of the negation. Won't be too heavy means “will not be too heavy,” not necessarily “will be light.” Won't all get a seat means “not everyone will get a seat,” not “nobody will get a seat.”
Subject + will not / won't + base form of the verb. / Subject + am/is/are + not going to + base form of the verb.
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
- V1 / base form —
- The base verb without to: work, go, be.
We won't be late for the meeting.
We won't be late for the meeting.
The future lateness is negated; won't = will not.
This box isn't going to be too heavy.
This box isn't going to be too heavy.
The negation concerns excessive weight. The box may still be heavy.
7. Questions and short answers
To ask about a prediction, move will or am/is/are before the subject. Do not add do or does to a direct question with will.
In a short answer, repeat the required auxiliary verb: Yes, it will. No, it won't. Yes, we are. No, we aren't. A standard short affirmative answer does not end with a contracted auxiliary verb: Yes, we are, not Yes, we're.
Will + subject + base form of the verb? / Am/Is/Are + subject + going to + base form of the verb?
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
- V1 / base form —
- The base verb without to: work, go, be.
Will the tickets be expensive? — No, they won't.
Will the tickets be expensive? — No, they won't.
Will comes before the tickets; they replaces the tickets in the answer.
Are we going to be late? — Yes, we are.
Are we going to be late? — Yes, we are.
The question begins with are, so the short answer also contains are.
8. From context to your own sentence
First decide exactly what you are predicting: an event, a state, the absence of an event, or an answer to a question. Then separate the basis in the present from the result in the future.
Give a short, clear prediction using will or going to. If a present sign is important, name it separately. Do not add unknown causes or change the participants, numbers, or words such as very, too, and all.
When checking your work, compare more than just the words with the model: Is the meaning preserved? Is the construction correct? Does it meet an explicitly stated requirement? A natural rephrasing can also be correct.
There are only two seats left. We won't all get a seat.
There are only two seats left. We won't all get a seat.
If there are five of us, this is an appropriate prediction. It does not mean that nobody will get a seat.
The new library is almost ready. It's going to open soon.
The new library is almost ready. It's going to open soon.
Its current state of readiness supports the prediction. The sentence does not give an exact opening date.
Common mistakes
Incorrect:It will rains tonight.
Correct:It will rain tonight.
After will, use rain without -s.
Incorrect:The water going to spill.
Correct:The water is going to spill.
In a complete sentence, is is needed before going to.
Incorrect:They is going to miss the train.
Correct:They are going to miss the train.
They agrees with are, not is.
Incorrect:Does the room will be cold?
Correct:Will the room be cold?
A direct question with will does not need does; put will before the subject.
Incorrect:She is going to likes the course.
Correct:She is going to like the course.
Use the base form like after going to.