1. It took him half an hour to walk to thestation.

--> He spent half an hour walking to the station 

2. Jenny left the office , then we arrived there

--> Before we arrived the office, Jenny had left there

3. Linda had finished her work before she went home .

--> After Linda had finished her wrok, she went home

4. He started writing novels when he was 19 year old.

--> He has written novels since he was 19 years old 

5. This is the first time I have watched such romantic movie.

--> I have never watched such romantic movie before

6. Thank you for showing me the way. It was very kind .

--> It was very kind of you to show me the way 

@linhhuong

1) He spent half an hour walking to the station 

2) Before we arrived the office, Jenny had left there

3) After Linda had finished her wrok, she went home

 4)He has written novels since he was 19 years old 

 5) I have never watched such romantic movie before

 6) It was very kind of you to show me the way