Rewrite the sentences using the word(s) in brackets. Do not change the form of the given words

XIV. Rewrite the sentences using the word(s) in brackets. Do not change the form of the given words.
(5 points)
1. He studies very hard. He doesn’t want to fail the final examination. (so that)
______________________________________________________________________________
2. Keeping the environment clean is very important. (to)
______________________________________________________________________________
3. Minh has collected stamps since 2000. (began)
______________________________________________________________________________
4. Mount Everest is the highest mountain in the world. (higher)
______________________________________________________________________________
5. I will be fifteen years old next week. (fifteenth)
______________________________________________________________________________