根据句意，用括号内所给单词的适当形式填空。

1. Yu Fang's brother is a ________(success) engineer.

2. I'll be able to finish the homework ________(easy) by noon.

3. The little girl came to the city for the first time and got _______(lose).

4. Life seems so _______(fair) to someone sometimes.

5. Education is one of the most important parts of a country's ________(develop).