Краткое пояснение: Используем ago для указания времени в прошлом, а for - для указания периода времени.
- Helen arrived in Ireland three days ago.
- Helen has been in Ireland for three days.
- Lynn and Mark have been married for 20 years.
- Lynn and Mark got married 20 years ago.
- Dan arrived an hour ago.
- I bought these shoes a few days ago.
- Silvia has been learning English for six months.
- Have you known Lisa for a long time?
Ответ: смотри решение выше