Playing QQ's "Happy Farm" by planting, watering, fertilizing, spraying, harvesting and selling of virtual vegetables, fruits and flowers, we can find out _____ all the excitement is about.
A giant helium(氦) balloon is telling residents of Paris how good or bad the air quality is.When it's good, the balloon ----measuring 22 meters wide and 32 meters high---shines green._________, it's red.