1 - I've written to them three times, but they haven't replied yet.
2 - I've asked you again and again but you haven't done it yet.
3 - I lent him 10$ last month but he hasn't given it back yet.
4 - He lost his pen a week ago but he hasn't found it yet.
5 - He borrowed my book last year but he hasn't given it back yet.
6 - She went to New York six months ago but she hasn't returned yet.
7 - She gave me $2 a week ago but I haven't returned it yet.
8 - I finished reading my library books a long time ago but I haven't changed them yet.
9 - She went to the bus-stop half an hour ago but the bus hasn't come yet.
10 - He's still studying that lesson but he hasn't learnt it yet.