5. My sister ............ since eleven o'clock
is swimming
have been swimming
has been swimming
6. Our coach ............. us for several years
trains
has trained
has been training
7. They ....... back after competition.
has just come
have just come
came
8. Sam ........... golf before
has been playing
has played
played
9. His father........... on horseback for an hour
has been riding
has ridden
rode
10. Alice ........... in that park yet.
haven't ran
isn't running
hasn't ran
11. We .......... this football match on TV.
have been seeing
has been seeing
have seen
12. These workers ......... that gym for two years.
have been repairing
have repaired
are repairing