1. She started working as a secretary five years ago  2. Helen started to learn Chinese in 2000.  3. I began to study French when I was six 4. They began living together last month  5. Nicky stopped smoking in 1997.  6. Susan have taken part in this activity   

1 She has worked as a secretary for 5 years

2 Helen has learned Chinese since 2000

3 I have studied French since I was six

4 They have lived together since last month

5 Nicky hasn't smoked since 1997