based on 3I ex.1
Use when, before or after, the past perfect and the past simple to join the sentences, as in the example.

1. The scientist made an announcement. He completed his research.
   [ ]
2. She got a degree in Engineering. She studied for four years.
   [ ].
3. He worked as a sales assistant. He got a new job as a car salesman.
   [ ].
4. Ann and David were engaged for five months.They got married.
   [ ].
5. Mr. Harris went to hospital. He was sick for many weeks.
   [ ].