Present perfect + since/for

I have lived in London ___ six months.

• For

• Since

I have danced ballet ___ I was small.

• for

• since

She hasn't had a day off ___ three months.

• for

• since

I've lost so much flexibility ___ I injured my leg.

• since

• for

They have all improved in attitude ___ the headmaster talked to them.

• for

• since

Wars have been happening ___ centuries, it won’t ever change.

• for

• since

I haven't been on holiday ___ ages.

• since

• for

I haven't eaten that much ___ Christmas.

• since

• for

I haven't been on holiday ___ last year.

• for

• since

She hasn't seen her jacket ___ yesterday, I think she lost it.

• since

• for