1. 1) more beautiful
2) the oldest
3) the difficultest
4) the best
5) more dangerous
6) the worst
7) more exciting
8) easier
9) cheaper
10) the most
4. 1) Russia is the biggest country in the world.
2) Playing chess is more boring than playing tennis.
3) Her hair is longer than mine.
4) This is the most interesting movie of the year!
5) My sister is 7 years older than me.