Fill in the gaps with the verb in brackets using the past perfect continuous.
Example: Sam gained weight because he _______ for 2 years. (overeat)
Answer: Sam gained weight because he had been overeating for 2 years.
1) When the boss came back, I _________there for 6 months. (work)
2) We _________ there for more than two hours when she finally arrived. (wait)
3) Mike wanted to sit down because he _______ all day at work. (stand)