1a. He was talking on the phone for over an hour.
1b. He is talking on the phone for over an hour.
2a. They were playing chess for two hours.
2b. They are playing chess for two hours.
Are all correct tense wise?
Thanks.
1a correct, though ‘talking’ is unnecessary: “He was on the phone” will suffice.
1b not possible. If you wish to indicate he is still on the phone, you would use ‘he has been on the phone…’ Alternatively, you would need to say something like
He is still on the phone, as he has been for over an hour.
Comments for 2 as for 1 regarding tenses.
The trouble with all these short sentences and requests for ‘correction’ is that no one has a clue of the setting. With a bit of imagination a case could be made for the ‘correctness’ of all the sentences.