Раскройте скобки, поставив глагол в Present Perfect или в Past Simple.
1.Unfortunately people (not/have) mobile phones in the 1960s.
2.This is the most difficult (I/ever/do)
3.(it/stop) raining yet?
4.She (become)a vegetarian a few years ago.
5.He (not/play) volleyball since he was a student
6.When (you/start)doing sport seriously?