Past Continuous VS Present Perfect Continuous

We use was (for I, he, she, it) or were (for we, you, they) as an auxiliary verb and the main verb has the ending -ing. This structure does not much change in the affirmative, interrogative and negative sentences.

​

I was looking at my watch when this happened. - Was I looking at my watch when this happened? - I wasn't looking at my watch when this happened.

Children were growing. - Were children growing? - Children weren't growing.​

There are four options of usage the Past Continuous Tense:

1) ​an interrupted process: We were running when she fell.

2) ​a long-lasting action: Everyone was sitting quietly.

3) ​a repeated action: You were feeding birds after work.

4) ​changes or growth: Her hair was going gray.

There are four options of usage the Past Continuous Tense:

1) ​an interrupted process

2) ​a long-lasting action

3) ​a repeated action

4) ​changes or growth

It is made up of two elements: the Present Perfect and the Present Continuous. So we have a compound auxiliary verb have been (for I, you, we, they) or has been (for he, she, it) and the main verb with the ending -ing. The structure does not change much in the affirmative, interrogative and negative sentences.​

They have been watching TV all day. - ​Have they been watching TV all day? - They haven't been watching TV all day.

​She has been running. - Has she been running? - She hasn't been running.

We use it in two cases:

1) ​actions started in the past and continue in the present: They have been watching TV all day (and they still are doing this).

2) ​actions have just finished but we are interested in the results: She has been running (this is why she is breathing so hard).