We use the Continuous Verb Forms to talk about things which are happening over a period of time. With continuous forms we highlight the duration of an event.
Note that sometimes we use the word Progressive instead of Continuous.
Continuous forms usually talk about things which are happening for a while only – they will stop sometime.
I am living in New York right now but I don’t know where I will be next month.
Verbs in continuous forms always express actions that are taking place during a specific time in the present, past or future.
So a verb in the Present Continuous usually expresses an action taking place at the present moment.
Quiet, please! I’m listening.
What are you doing with that hammer? I’m hanging a picture.
The Past Continuous is used to express an action taking place during another action in progress at the time.
She was crying while the police were taking her husband away.
or to express an action in progress interrupted by another action in the past.
I was watching TV when he called.
The Future Continuous is used to express an action expected to be taking place during another relative time in the future.
I will be taking my driving test tomorrow. Do you have any advice to give me?
Perfect verb forms can also be expressed in the continuous form.
Some verbs contain in their meaning an idea of permanency and because of this they are not used in the continuous form. For example, when we use the verb like, we are talking about a feeling we have which will last for a long time:
I like football.
She does not like boring books.
Do they like living in London?
For this reason, we do not usually use like in a continuous form.
There are other verbs generally used only in simple verb forms, for example:
verbs of mental activity: know, understand, think
verbs of emotions: like, love, hate, desire
verbs of senses: see, smell, touch, taste, hear
verbs of possession: own, belong, possess, have
verbs of reporting: say, tell, ask, answer
miscellaneous verbs: need, contain, depend, consist
With verbs of perception we can often use can:
I can hear him but I cannot see him.
Can you smell the roses?
We can use some of the verbs listed above in continuous forms but their meaning changes when we do. They refer not only to what is happening right now but they also tells us it is an active effort:
What are you thinking? – I am thinking about our holiday.
We never use have in a continuous way to mean possession. If however we want to give the idea that we are making an active effort then we can use have in the continuous form:
I have long hair. (simple form)
I am having my hair cut. (continuous form)
Verb Tenses & Forms in English Grammar – an overview of all the verb forms & tenses.