The professor____________ the questions to the students already. ( has explained, explains )
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I____________ to repair the car while you were watching TV. ( am trying, was trying )
They went to have their dinner after they____________ the assignment. ( finished, had finished )
The bridge____________ by the time you come back from abroad. ( be built, will have been built )
She____________ me that she would be very happy to have us in her home. ( told, tells )