Complete the sentences with the correct forms of the verbs in the brackets. Use the past perfect continuous.
1. Orla felt fit for the marathon because she (exercise) a lot.
2. When I went to see Ms Winter, her secretary told me that she (speak) on the phone for two hours.
3. When I noticed my mistake, I (drive) for an hour in the wrong direction.
4. He (take) the dog for a walk for two hours yesterday.