TENSES

PRESENT PERFECT CONTINUOUS

Present perfect continuous, form
The present perfect continuous is made up of two elements: (a) the present perfect of the verb 'to be' (have/has been), and (b) the present participle of the main verb (base+ing).

Subject	has/have been	base+ing
She	has been	swimming

Affirmative
She has been / She's been	running
Negative
She hasn't been	running
Interrogative
Has she been	running?
Interrogative negative
Hasn't she been	running?

Example: to live, present perfect continuous

Affirmative	Negative	Interrogative
I have been living	I haven't been living	Have I been living?
You have been living	You haven't been living	Have you been living?
He, she, it has been living	He hasn't been living	Has she been living?
We have been living	We haven't been living	Have we been living?
You have been living	You haven't been living	Have you been living?
They have been living	They haven't been living	Have they been living?

Present perfect continuous, function
The present perfect continuous refers to an unspecified time between 'before now' and 'now'. The speaker is thinking about something that started but perhaps did not finish in that period of time. He/she is interested in the process as well as the result, and this process may still be going on, or may have just finished.

Examples:

1. Actions that started in the past and continue in the present.

a. She has been waiting for you all day (=and she's still waiting now).

b. I've been working on this report since eight o'clock this morning (=and I still haven't finished it).

c. They have been travelling since last October (=and they're not home yet).

2. Actions that have just finished, but we are interested in the results:

a. She has been cooking since last night (=and the food on the table looks delicious).

b. It's been raining (= and the streets are still wet).

c. Someone's been eating my chips (= half of them have gone).

Note:

Verbs without continuous forms
With verbs not normally used in the continuous form, use the present perfect simple. See list of these verbs under 'Present Continuous':

• I've wanted to visit China for years.
• She's known Robert since she was a child.
  
• I've hated that music since I first heard it.
  
• I've heard a lot about you recently.
  
• We've understood everything we've heard this morning.