He said that he had visited the park _____.
The water of the Miyun Reservoir is regularly ______ to ensure the security of Beijing people’s drinking water.
It wasn’t until he was diagnosed with cancer ______ he realized the significance of health.
The sign over there says that no person ______ enter the area without official permission.
Ten years ago the population of our village was ______ that of theirs.
The English spoken in the United States in only slightly different from ______ spoken in England.