Rewrite the sentences. Use items from C to rewrite the underlined parts of the sentences in a more formal academic style.

1. The information lies in archives that must not be opened until 2050.
2. He thought up his theory while still a young man.
3. Each of the symbols in the phonetic alphabet stands for a sound.
4. This study went against what was previously held to be true, and so started a great deal of discussion amongst specialists in the field.
5. Details of the experiment have been added at the end of the report.
6. Jelowski's book thinks about the rise and fall of great Empires over two millennia. She sees the Roman Empire as an example of a pattern that has repeated itself in other times and other parts of the world.