Present continuous - I'm working at the moment.
Past continuous - Jack was cooking dinner when I arrived.
Future continuous - I will be playing tennis this time tomorrow.
Present perfect continuous - She's been working her for three years.
Generally, continuous (or progressive) tenses are used to describe what is happening at a particular moment in time. The focus when using continuous tenses is always on an action in progress. However, there are some important exceptions to using continuous tenses. Most importantly, there are a number of common non-continuous verbs that are never or rarely used with continuous forms. These verbs fall into a few categories:
Mental and Emotional States
She dislikes that boy.
NOT She is disliking that boy.
Jack prefers going out for dinner tonight. NOT Jack is preferring going out for dinner tonight.
I recognize you! NOT I'm recognizing you!
I saw him when the train arrived. NOT I was
seeing him when the train arrived.
It tastes strange. NOT It is tasting strange.
Did you hear that? NOT Were you hearing that?
You astonish me! NOT You are astonishing me!
I'm afraid I disagree with you. NOT I'm afraid I am disagreeing with you.
I meant to tell him yesterday afternoon. NOT I was meaning to tell him yesterday afternoon.
It depends on how much it costs. NOT It is
depending on how much it is costing.
She said it involved a lot of work. NOT She said it was involving a lot of work.
It doesn't matter. NOT It isn't mattering.
There are also a number of verbs that don't take the continuous forms in one meaning but DO take the continuous forms in other meanings. Here are some of the most important:
feel = 'have an opinion' - He feels he should
get a second chance.
see = 'understand' - I see what you mean.
think = 'have an opinion' - I think we should leave immediately.
appear = 'look like' - That appears to be stale.
look = 'seem' - It looks impossible!
taste = 'have a taste' - That tastes yummy!
feel = 'feel physically' - I'm feeling awful
see = 'visit' - She's seeing a doctor this morning.
think = 'use the brain' - He's thinking hard about the problem.
appear = 'be on stage / perform' - Jack Daniels is performing at the Paramount tonight.
look = 'stare at' - I'm looking at that strange man.
taste = 'use the mouth' - The cook is tasting the sauce!
Resource: Beare, K (English as Second Language)