Fill in the following sentences by using PAST PERFECT CONTINUOUS or PAST PERFECT:
1.She … (just / go) out when I called her.
2.I was exhausted because I … (work) for a long time.
3.He … (live) in London since 2010.
4. Linda played tennis after she … (do) her homework.
5. My brother … (eat) all the pie before we got back.
6. He was tired because he …. (write) letters all morning.