50. You won’t be able to see him because he ______ a meeting in Suzhou when you arrive.
It is acknowledged that ___ shortest distance between persons is ___ sincere smile..
Life is like a long race where we __________ others to go beyond ourselves.
Both the Winter and Summer Olympics are held ___________on a regular basis.
What do the five rings on the Olympic flag ___________?
Visitors were _______ at the ________pictures that the guide showed.