perfect tenses: for or since?

Do you know the difference?

It can be quite tricky to know which one to use and just like everything else, you need to practise!

In the following sentences, should you use 'for' or 'since'.

• 1. I have lived in London ___ six months.
  
  since
  for
  
• 2. I have danced ___ I was small.
  
  for
  since
  
• 3. She hasn't had a day off ___ three months.
  
  since 
  for
  
• 4. I've lost so much flexibility ___ I injured my leg.
  
  since
  for  
  
• 5. They have all improved in attitude ___ the headmaster talked to them.
  
  since
  for 
  
• 6. Wars have been happening ___ centuries, it won’t ever change.
  
  for
  since 
  
• 7. I haven't been on holiday ___ ages.
  
  for
  since  
  
• 8. I haven't eaten that much ___ Christmas.
  
  since
  for  
  
• 9. I haven't been on holiday ___ last year.
  
  since
  for
  
• 10. She hasn't seen her jacket ___ yesterday, I think she lost it.
  
  since
  for