Look out for time phrases and when you use ‘for’ and ‘since’ with them in the article. Below there is an explanation of ‘for vs since’. 
FOR vs SINCE
We use for or since to say how long something has happened for.
For
We use for when we give the length of time e.g. for 3 days, for 2 months, for 5 years
Since
We use since when we give the beginning of the time e.g. since Thursday, since yesterday, since 2009, since last week, since July
For vs Since
| For | Since |
|---|---|
| I’ve known her for 10 years | I’ve known her since 2001 |
| I’ve had this phone for 6 months | I’ve had this phone since April |
| I’ve been learning English for a very long time | I’ve been learning English since 2000 |
Ago
Ago goes after a time expression. It’s September 19th now. I came back to Berlin 3 weeks ago. I’ve lived here for over 2 years, since March 2009. By the way, this is a perfect example of a news story that will appear in virtually every national newspaper around the world. You can use these articles to practise your English. First read the news in your own language and then from a British newspaper. The advantages of this are explained here in my earlier blog