26. The students have never used such a modern laptop before.
→ This is the first time the students __have used such a modern laptop___
→ This is the most modern laptop the students have used____
27. He stopped emptying the ashtray two weeks ago.
→ The last time he _emptied the ashtray was two weeks ago._________________
→ He last emptied the ashtray two weeks ago.

26. The students have never used such a modern laptop before.
→ This is the first time the students __have used such a modern laptop___
→ This is the most modern laptop the students have used_such a modern laptop before.___
27. He stopped emptying the ashtray two weeks ago.
→ The last time he _emptied the ashtray was two weeks ago._________________
→ He last emptied the ashtray two weeks ago.