Ответ:
1 They have just appeared on the stage.
2 I have never been to Australia.
3 Marry will have finished her work by the next week.
4 She had prepared all necessary things before the classes began.
5 We have already discussed this problem.
1 She returned home at 9 o’clock yesterday.
2 Good students go to the Institute every day.
3 I was writing an exercise when they came in.
4 Marry has already finished her course work.
5 We will have learnt many new English words and expressions by the end of the next term.