1.He sings well. A lot of people admire him. (Double comparative)
=> The better he sings, the more people admire him.
2. The woman was very friendly. She served us dinner. (Relative pronoun)
=> The woman who served us dinner was very friendly.
3.The boy's wallet was stolen. He called the police. (Relative pronoun)
=> The boy whose wallet was stolen called the police.
4.She visited many countries. She had lots of friends. (Double comparative)
=> The more countries she visited, the more friends she had.
5.My father was very pleased. I passed the entrance exam with high points. (Adjective+that clause)
=> My father was very pleased that I passed the entrance exam with high points.