Main points

* Continuous tenses describe actions which continue to happen before and after a particular time.

* Continuous tenses can also indicate duration and change.

1 You use a continuous tense to indicate that an action continues to happen before and after a particular time, without stopping. You use the present continuous for actions which continue to happen before and after the moment of speaking.
I’m looking at the photographs my brother sent me.
They’re having a meeting.

2 When you are talking about two actions in the present tense, you use the present continuous for an action that continues to happen before and after another action that interrupts it. You use the present simple for the other action.
The phone always rings when I’m having a bath.
Friends always talk to me when I’m trying to study.

3 When you are talking about the past, you use the past continuous for actions that continued to happen before and after another action, or before and after a particular time. This is often called the `interrupted past’. You use the past simple for the other action.
He was watching television when the doorbell rang.
It was 6 o’clock. The train was nearing London.

WARNING: If two things happened one after another, you use two verbs in the past simple tense.

As soon as he saw me, he waved.

4 You can use continuous forms with modals in all their usual meanings.
See Units 79 to 91 for more information on modals.

What could he be thinking of?
They might be telling lies.

5 You use continuous tenses to express duration, when you want to emphasize how long something has been happening or will happen for.
We had been living in Athens for five years.
They’ll be staying with us for a couple of weeks.
He has been building up the business all his life.
By 1992, he will have been working for ten years.

Note that you do not have to use continuous tenses for duration.
We had lived in Africa for five years.
He worked for us for ten years.

6 You use continuous tenses to describe a state or situation that is temporary.
I’m living in London at the moment.
He’ll be working nights next week.
She’s spending the summer in Europe.

7 You use continuous tenses to show that something is changing, developing, or progressing.
Her English was improving.
The children are growing up quickly.
The video industry has been developing rapidly.

8 As a general rule, verbs which refer to actions that require a deliberate effort can be used in continuous tenses, verbs which refer to actions that do not require a deliberate effort are not used in continuous tenses.
I think it’s going to rain. (`think’ = `believe’. Believing does not require deliberate effort)
Please be quiet. I’m thinking . (`think’ = `try to solve a problem’. Trying to solve a problem does require deliberate effort)

However, many verbs are not normally used in the continuous tenses. These include verbs that refer to thinking, liking and disliking, appearance, possession, and perception.
See Unit 62 for lists of these verbs.