Ответ:
1.My sister has been using this shampoo for 2 years.
2.He has been skipping breakfast since he has been student.
3.Mu aunt has been eating much chocolate since her childhood.
4.Nick has been cleaning his teeth with a new toothpaste since yesterday.
5.I have been preparing for the English exam since last week.
6.They have been going to the swimming pool since last month .
Можете отметить мой ответ как лучшее ?!