1 I haven't visted Oslo since 1998
=> The last time i visted Oslo was in 1998

2 It took him two days to decorate the living room (Spent)
=>He spent two days decorating the living room.

3 She speaks Russian better than her sister (AS)
=>Her sister doesn’t speak Russian as well as she does

4 The boy is too short to reach the book on the shelf (Enough)
=>The boy is not tall enough to reach the book on the shelf.

5 I don't play tennis as well as you do
=> you play tennis better than I do

6 I haven't been to the dentist's for two years
=> the last time i had been to the dentist's was 2y ago