2)
1. He was always singing along to music that he heard on the radio.
2. Leslie had started playing Tchaikovsky's Piano Concerto No. 1, after hearing it only once before.
3. When Dustin Hoffman saw a programme about Leslie L on TV, he decided that he wanted to plat an autistic savant in a film.
3)
1. Scientists have tested many rainforest plants for a cure for cancer.
<em>Many rainforests plants have been tested for a cure for cancer by scientists,</em>
2. People are destroying huge areas of rainforest every day.
<em>Huge areas of rainforest are being destroyed every day.</em>
3. Scientists are developing medication from frog poison.
<em>Medication from frog poison is being developed by scientists.</em>
4)
1. My friend, who love helping people, wants to become a psychologist.
2. This is the book which our teacher was talking about.
3. Many experts will attend the conference where new theories will be presented.
5)
1. The aliens claimed that they could destroy our planet.
2. The commander warned us that our spaceship would land soon.
3. My friend promised that she would be at the club by five o'clock
