In these following sentences, which one is grammatically correct?
They were playing football since 10 o'clock.
They had been playing football since 10 o'clock.
According to this reference link:
Past Perfect Continuous Tense is used to express a continued or ongoing action that started in past and is continued until sometime in past. There will always a time reference like – for a few days, for ten months, for 2 years, since Wednesday, since 2011, since January etc. If there is no time reference, then it is not a Past perfect continuous tense. Without time reference, it is Past Continuous Tense.
But I saw the following example, which has used with time reference.
So, I am confused between past continuous and past perfect continuous. Please someone help me.
Thanks in advance.