Resposta:
1)
- He has been here for fifteen years
- She hasn't played tennis since she was four years old
- I have lived here since I was a child
- They have the same car for a very long time
- They have known each other since they were at university
- We haven't seen John for weeks and weeks
2) as frases 3, 4, 6 e 7 não há erros / 5 - since / 8 - for
3)
- for 15 years / since I got married
- have you known / for over 10 years / since I was a child
- have you studied / for 3 years / since I joined the online course
- have you had / for 8 year / since I was in elementary school
Explicação:
since = desde
for = por
