--- Did your father come back early last night?--- Yes. It was not yet eight o’clock _______ he arrived home.
Please excuse me _______ your letter by mistake.
After describing the planned improvements, she went on _______ how much they would cost.
The film star walked to his car, ______ a crowd of journalists.
_______ on time, this medicine will be quite effective.
When I handed the report to John, he said that George was the person _______.