_________ March 28, about 20 Chinese cities turned off lights of major buildings for one hour.
-- How about ____ Christmas evening party? -- I should say it was ____ success.
— Would you like to go hiking with us?— ________. I’m preparing for the coming exams.
— Excuse me, could you tell me ________ to fly to Guilin?— About two hours.
The boy isn’t old enough ________ with the difficult problem by himself.
Not only Susan but also Sandy _________ abroad for traveling. They will return next Sunday.