1. He has lived in the city since 2007.

Question

2. He has lived in the city since he was 2 years old.
3. He has lived in the city since two years ago.
4. He has lived in the city for two years.
5. He has lived in the city since he moved to the city.
6. He has lived in the city since he moved to the city when he was a little child.
7. He has lived in the city for a while.
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Are the sentences all grammatical? Which ones are not acceptable in terms of grammar?

Answer 1

5 is awkward and unnecessary.

6. He has lived in the city since he moved there when he was a child.

The rest are fine.