10. Lately I (think) about changing my career because I (become) dissatisfied with my job.

11. Bob (run) 10 km.

12. The dog (bark) since midnight.

13. We (miss) the bus twice this week.

14. The birds (already/fly) to the South.

15. Mike (forget) to learn his poem.

16. David (paint) in his studio since 10 o’clock.

17. Mary and Sam (collect) stamps for 3 years.
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