At a beach or a swimming pool a lifeguard is a person who is responsible for __________ other swimmers and protecting them from accidents.
She will get a divorce from her husband unless _______.
It is the test system, _____ the teachers, that is to blame for the heavy burden of middle school students nowadays.
______ not to miss the flight at 15:20, the manager set out for the airport in a hurry.
The last letter ____ arrived yesterday morning left him______ very sad.
The opening ceremony of the 29th Beijing Olympic Games was _____ that everybody was greatly impressed_____ it.