1) Before her guests arrived, she had already cooked dinner. 2) By the time Jane came back home, her brother had helped her with cleaning. 3) She was sad because she had lost her money. 4) He felt really happy because he had eaten his favourite cake. 5) He went to the cinema after he had done his homework.

1) Had already cooked the dinner
2) her brother had done his homework
3) she had failed her driving exam
4) he had made his girlfriend a proposal.
5) he had realized that he had enough money for it