Rewrite the following sentences with the given information.
11. They have studied at this school for seven years.
=> They began ...............................................................................................
12. This is the first time I have watched this film.
=> I haven’t....................................................................................................
13. I have never attended such an enjoyable wedding party before.
=> This is the first time ................................................................................
14. I haven’t met him for ten years.
=> I last ............................................................................................................
15. They last visited me five years ago.
=> They haven’t ..............................................................................................