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Unit 18 :
For/ Since / Ago
Elementary
Summary
Since, for and ago: talking about periods of time
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for & since
Jack is in Brazil. He has been there for three days/ since Monday.
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ago
> ago = before now (現在之前)
- Benny started his new job three days ago. (= three days before now.)
- “When did Betty leave?” “Twenty minutes ago.” (= twenty minutes before now.)
- I had lunch an hour ago.
- Life is very different a hundred years ago.
> ago = use in past tense (started/did/had/was …)
* Compare with “ago” and “for”:
1) When did Albert arrive in London?
He arrived in London three days ago.
2) How long has he been in London?
He has been in London for three days.