Radar enables the pilot of an airliner to take off, fly and land in _____.
--Do you want me to help you with the cleaning?--No, Lisa. I can manage, but ___.
At the railway station, the mother waved goodbye to her daughter until the train was ___.
After the long journey, the three of them went back home, ___.
It is reported that the Group of Eight (G8)___ the eight richest countries in the world.
It ___ to chat online all day long. You’d better do something else.