Mr. Green drove slowly on the way home until he reached the high way, ______ the speed limit was 60 miles per hour.
With the successful launch of Tiangong-l, which was _____ breakthrough in space field,China's space dream took a step closer to _____ reality.
He is sure to ________ with the help of Mrs. Li.
Every year he ________ to Beijing to visit his teacher.
The last bus has left; ________, you’ll have to walk there.
He ran ________ fast that I couldn’t catch up with him.