"Some of the staff are/were late."
Can one both use the present tense as well as the past tense in this sentence ? I would say yes. Correct ?
It all depends on context, as always. For example:
If it's 9.15am and not all the staff who are scheduled to arrive for a meeting at 9am are there yet, then it's "Some of the staff are late".
The next day, when relating the story to someone else, it would be "The meeting was due to start at 9am but at 9.15, only four of us were here. Some of the [other] staff were late."