Task 1.
1) news; 2) competition; 3) chance; 4) won; 5) lucky; 6) chance in a million; 7) participants; 8) luck; 9) prize; 10) tour; 11) world; 12) wood.
Task 2.
1. successful
2. funny
3. Russian
4. creative
5. helpful
Task 3.
1. each other
2. travelling
3. closing
4. speak
5. one another
Task 4.
1. clean
2. is cooking
3. will win
4. asked
5. wrote