He finds ____ hard to finish the work in two days.

____from Adelaide to Darwin and you’ll observe some of Australia’s most beautiful landscapes.

________peoplewenttotheconcertlastweek.

Another drug that has helped improve people’s health is penicillin, _________ is _________ by many _________ one of the most important medicines.

The movie is about a true story ______ happened in Tang Shan in 1976.