Nearly four hundred supermarkets in Beijing are preparing to dim(使暗淡) their lights ________ the "Earth Hour 2010" on Saturday night.
It is considered a good way for students to ________study with pleasure.
It is known to all that a proper amount of exercise ________ to good health.
I have read the material several times but it doesn't make any ____ to me.
After staying in hospital for long, the patient was advised to go to the seaside to___ his health.
Australian English differs ___ British English ___ that some of the vocabulary has special meanings.