Use Past Simple and Past Perfect Continuous
1. Yesterday he was very busy since he was fixing the TV from noon.
2. He left for the day before I arrived. He waited for me almost a week. To regret, I couldn't come earlier.
3. When Anna entered the living room, everyone was laughing. Mr. Smith was telling funny stories for 15 minutes.
You give these a try, and someone will check your work for you.
Simple past = walked, said, rang, studied, cut (without any helping verbs)
Past perfect continuous = had been walking, had been saying, had been studying, had been cutting
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